Avoid Contractor Allowances

Allowances & Tips on Bid and Quotation Comparison

Allowances have created more problems between homeowners and contractors than you can imagine. Often they manifest themselves as financial time bombs that explode in the middle of a project. Sometimes they create enormous heartache when customers find out that the items they would really like to have are 100 to 200 percent over budget.

Allowances are cost items for products or services in a construction project that have yet to be specified or defined. You can compare them to a budget number on a financial forecast. Herein lies the problem with allowances. You 'hope' that you can get what you want for the specified number. Basing financial expectations on 'hope' is a very dangerous thing to do.

However, there are instances when allowances can be used successfully in a project. It requires skill, honesty, and timing on the part of the contractor for allowances to become an asset.

Confusion

Allowances have been known to create vast amounts of confusion when attempting to compare quotations from several different contractors. For example, let's assume that two contractors quote allowances and one specifies the exact item he will use with no price attached to it. You are forced to find out his cost and then perform mathematics to equalize the three different quotations. If you make a mistake, you may end up selecting a contractor who doesn't represent the best value.

Working with allowances also creates another major problem. You can start a job and be unsure of the final quality and cost of the items you intend to use. A contractor may misrepresent (either on purpose or by mistake) what an item or group of items really costs. Unfortunately, you find out after the project has started and possibly open yourself up to disappointment. I have seen it happen in many instances where people have had to settle for a lesser quality item because what they wanted cost too much.

These same people could often have had what they wanted if they had known the true cost in the beginning. They could have either borrowed more money from the bank, or adjusted some other aspect of the project to accommodate the allowance overage.

Dishonesty Factor

Some contractors are notorious for using allowances as an effective selling tool. These contractors attempt to include as many allowances as possible in their quotations. Often, they set artificially low numbers as the allowance figure. This practice almost always ensures that their quotation will show the lowest price. Those individuals who shop for price fall for this ploy virtually every time.

However, reality sets in after the contract has been signed or several days or weeks into the job. At this point it is too late to 'fire' the contractor. He or she knows this. You are then forced to scramble to raise the additional funds to purchase the items you need.

Losing Proposition

Allowances pose another problem that many homeowners overlook. This problem can result in a windfall profit for a builder or subcontractor or create another hidden charge. Here is the problem.

Let's say your architect or your plans call for a whirlpool tub or some other large item to be installed in your project. Whirlpools come in many different sizes and weights. The plumber bidding the job (if he /she has been in the business longer than 90 days) will probably assume that you will wind up selecting the heaviest, most complicated whirlpool made. He will base his/her price on this assumption. If you select a lightweight, easy-to-install whirlpool, what chance do you think that you will receive a rebate? My guess is less than 1 in 10.

In fact, if you are dealing with a bold and extremely dishonest plumber and contractor, you can get double charged! Assume that you do pick the whirlpool that the plumber thought you would. He or she can tell you that they figured on putting in a lightweight, easy one. This person will then tell you that they need more money to install the one you selected. Trust me, I know of instances where this has happened. It is frightening to think that people are this dishonest. To make matters worse, this will happen thousands of times in the upcoming year to homeowners across this nation. Hopefully, it will never happen to you.

Allowances & Changes

Allowances can create another insidious problem. Imagine this scenario. Let's say that you have an allowance for a medicine cabinet. Let's further assume that your contractor is not as organized as he/she should be.

The rough framing proceeds as does the plumbing and electric rough-ins. At this point you begin your search for your medicine cabinet. After visiting the store, you select the jumbo medicine cabinet that has everything. Anyway, after delivering the dimensions to your contractor, he informs you the next day that pipes and wires must be moved to accommodate your choice. Guess who has to pay? It will be you 9 times out of 10, trust me.

Avoiding the Nightmares

How, you might ask, can these problems be avoided? It's simple. Preselect as many items as possible prior to completion of your plans and specifications.

If you are serious about your project and you are going to complete it, you will eventually have to make product selections. It is better to make them at the beginning of the project so that they can be discussed with the architect or project planner. Often certain things will need to be drawn on the plans to indicate how and where the items should be placed.

Also, selection of items before the project begins allows you vast sums of time to observe as your project is being built. You will eliminate all of those hectic last minute shopping trips.

The preselection of items also allows you to identify what items are special order items. This fact will be beneficial to your builder, especially if it is noted in the plans and specifications. A large majority of project delays can be blamed on special order items. Frequently, a homeowner makes a selection three weeks ahead of time before an item is needed on the job, only to find out that the item will take six to eight weeks to arrive! This happens every day somewhere in this great land!

The preselection of items prior to the start of construction allows you to assemble technical information regarding the correct installation of items. If you are interested, you can read this material and watch to make sure that the products are, in fact, being installed correctly. Everyone can make mistakes, including your contractor. You just might catch a mistake one day that otherwise might have gone unnoticed.

The elimination of allowances will provide you with very crisp numbers when your bids are presented. Because each contractor knows exactly what you want, there should be no surprises. In the event that he/she makes a mistake, there is virtually no place for them to manipulate the numbers.

Project delays should be kept to a minimum. Once again, the contractor knows what you want. You effectively place the ownership of the 'delay' problem solely on the shoulders of the contractor. He/she cannot blame you for making slow decisions or picking out a hard-to-get item.

Elimination of allowances also lets you or your contractor construct an accurate time-line regarding the scheduling of the entire project. Because you know exactly what is going to be installed, lead times on ordering, and correct installation times, a simple critical path method chart can be constructed. This chart will permit you and the contractor to accurately predict the completion date of your project.

Time Savers?

Architects and contractors often try to use allowances as 'time savers'. They indicate that projects can be started sooner by having you make selections as the project progresses. This is not always true. Tell me, do you think it is worth $500 to $1,000 to preselect items? One change order can easily cost this amount!

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Interior Door Installation Tips

Interior Door Installation - Time Saving Tips

Just recently, I transformed a customer's house in two days. The homeowner had decided that her plain hollow core interior doors were outdated. When she first contacted me, she was not thrilled about the prospect of tearing out the doors, frames and interior trim. I looked at her and indicated that most of that work was unnecessary. She at first thought I was kidding. I said that the frames were nice and square, the trim was in good shape, and that all she needed were doors. This news provided her with a windfall of extra money. She upgraded to the next level of designer door. Needless to say, she was delighted.

Instant Gratification

There are literally millions of houses built in the 1950s, 60s and 70s that have hollow core flush doors. They were popular during those time periods. One of the reasons they were popular was that it was just about your only choice! Only in the last five to ten years has there been a a wide variety of interior door styles.

Homeowners who are building new homes or remodeling existing homes now have a wide selection to choose from. You can get doors that are solid core as well as hollow core. Doors are available with different species of wood grains. Birch, oak, mahogany and other species are readily available. In fact, I am typing this bulletin on top of a damaged oak door which I use as a computer table! It is not simulated oak. It is the real McCoy!

This wide array of doors, styles, veneers, etc. coupled with the fact that a door can be changed out in as little as an hour enables you to completely change the feel of a room or an entire house in one day!

What's Really Involved?

OK, so you think you want to change out a door yourself. You realize that you are not a master carpenter. You back off. Not so fast! If your door frames are square and you can take accurate measurements, this job is doable. I'm serious.

Many lumber companies and home centers here in Cincinnati will gladly sell you a door that they can mill to your specifications. Mill to your specifications? Doors need to have holes drilled for locksets and mortises created for flush hinge installation. That's what milling is. You provide the "specifications" - locations of these holes and mortises.

The first thing to do is to make a little drawing of the room which the door serves. Draw the four walls and the door opening. Try to make it to scale. Draw the door on the plan in a partially open position. One side of the door (the hinge side) should be "attached" to one side of the opening on your drawing. Make sure it's attached to the right side!

Now you need to take some measurements with the door in the closed position. You need to be on the side of the door, when it's closed, so that you can see the hinge pins. This will enable you to measure the door at its widest point. You see, most interior doors have a slight bevel along the edge opposite the hinge edge. This bevel allows the door to close without banging against the frame. Without the bevel, the gap on the latch side of the door would be large and unsightly.

OK, enough about bevels. Measure the width of the door at the top, middle and bottom. Hopefully, it will be very nearly the same. The measurement should be very close to 30 inches, or 32 inches, or some other even number. It may be an 1/8th of an inch less or so. That's OK. Be sure to get an accurate reading down to the 1/8th of an inch. Draw a picture of the door and note the width on the drawing. Do the same thing for the height of the door. Take a reading at each end.

Now for the hinges. Open the door and measure from the top down. Note where each hinge starts and stops. Always measure from the top of the door. Do not measure from hinge to hinge!

The lockset is the only remaining measurement. We need two measurements for this. First, measure from the top down to the center of the lockset. Second, measure from the edge of the door to the center of the lockset. This second measurement will be one of two measurements in 99 percent of the cases: 2 3/8 or 2 3/4 inch. It is called the backset measurement.

Finally, use a framing square to check to see if the door is square. Check each top corner. If the top corners are square, you will be in good shape. If the bottom is not square because it was cut off for carpet or whatever, the lumber yard will figure this out from your top to bottom measurements.

That's Too Tough Tim!

So, you're a lightweight. You can't run with us big dogs. No problem! There is an easier way. Simply take the door off the hinges and offer it up as a sacrifice to the lumber company for a week. They will make an exact copy of the door for you. If you choose to do this, be sure to write in pencil, on both sides of the door, which is the TOP. Do this BEFORE you take the door off its hinges. More than one carpenter has reversed a door and milled it upside down!

I highly recommend that you consider an interior door remodel. You can really change the look and feel of your home with new doors. Your frustration with those flimsy hollow core doors will disappear when you close that new solid core three, four or six panel door!

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Interior Doors Manufacturers

Interior Doors Manufacturers

Following is a partial listing of interior door manufacturers. Many make similar style doors of similar quality. You may find a door style that you like from one company that matches one that you can easily obtain. You will be amazed at the selection!

  • Byrcon Wood Products 
  • Craftmaster Manufacturing, Inc. 
  • Doors by Decora 
  • Historic Doors 
  • JELD-WEN 
  • Masonite 
  • Simpson Door Company

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Installing Interior Pre Hung Doors

Pre-Hung Doors

Are you a weekend warrior who wants to install a new pre-hung door? Are you experiencing a little anxiety? As they say in Jamaica: No problem!

Let's assume that you created a large enough rough opening. I always make my rough openings two inches wider and three inches taller than the size of the door for standard interior door units. This gives you plenty of room to wiggle and shim the door.

If you took your time in the rough framing and used straight lumber, you should have no problems. Always hang a door starting with the hinge jamb. The rough jamb on the hinge side of the door should be plumb. If this is the case, you can nail the door jamb right to the rough jamb. If not, you will need to shim the hinge jamb to make it plumb.

I always use eight penny finish nails to nail the jamb. Do NOT nail the nails in all the way at this time! Leave them sticking out 1/4 inch in case you have to make adjustments. I put one nail equal in height at each hinge location and at each shim location.

Now let's start on the other jamb. But first, we need to look at the top jamb reveal. Stand on a bucket or a ladder. Look at the gap between the top of the door and the jamb. Is this gap equal? If not, the latch side jamb needs to go up or down to make this gap equal. Do what you have to do to make this gap equal.

The latch side jamb is shimmed to create a similar equal gap. I always shoot for a 1/8 inch gap. No larger! Usually the controlling measurement is what the gap is at the top of the door. The people who milled the door and door frame create this gap measurement. If they did their job right, you simply need to shim the door every 16 inches so the latch jamb is parallel with the edge of the door. Once again, when nailing, don't drive the nails all the way.

When checking for an equal gap, be sure to put pressure against the jamb. You may think the gap is equal, but will be surprised when you nail the jamb tight. Cedar shims can compress and mess up your gap. Be patient and all will go well. If you have to cut off the bottom of the door, be sure to paint or seal it immediately! This prevents warping.

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Entry Doors

Therma-Tru fiberglass door installed

Entry doors often reflect the personality of the people who live in a house. As such, exterior door manufacturers offer countless styles and options in today's residential entry door market.

Not only are different styles available, but different door materials as well. As recently as 30 years ago, wood was your only choice in residential doors. Now, you can choose from steel insulated doors, fiberglass and composite (combination of wood and fiberglass) doors and traditional wood doors.

Technological advancements for entry doors include weather resistant simulated wood finishes, multi-point locking systems, extensive decorative glass options, super insulated cores, superb weather stripping, etc. Who would have thought that exterior doors could have progressed this far in just 30 years!

Traditional Problems

Certain wood doors of the past were good performers. Wood, being a natural insulator, offered both beauty and an acceptable level of performance. However, wood doors when exposed to water and water vapor can become poor performers. Wood, when exposed to moisture, actually begins to move. This movement can cause the wood to twist, warp, expand, etc. These movements can cause a wood door to be too snug or too loose in its frame. These movements can fracture the finishes applied to wood doors.

Alternative Materials

In response to these problems, door manufacturers began to experiment with alternative materials. The first substitute material to be used was steel.

Steel doors appeared on the scene in the 1960's. They offered many benefits. Steel was dimensionally stable. In other words, when exposed to moisture, the steel did not expand, twist or warp. Steel could be embossed. This process allowed steel doors to be stamped so as to simulate the appearance of traditional six panel or cross buck designs often used in solid wood doors.

Steel was also very durable. Although steel could be dented, it sometimes offered a higher degree of security.

The downside of steel, however, was that one lost the look and feel of real wood. Talented painters, when given the opportunity, could grain the doors with blended paints and stains. But, these faux finishes were just that -fake.

Twenty Years Later....

Pressures in the marketplace from consumers lead to dynamic changes in entry doors during the mid-1980's. At that time, steel doors were increasing in popularity, however, people wanted a more realistic looking product.

Fiberglass doors were being developed at this time. Fiberglass offered a compromise to those who wanted the benefits of steel, but yet a wood looking door. Fiberglass was able to be stamped and embossed with an actual wood grain finish. Furthermore, these doors could be stained to look just like real wood. Foam insulation could also be added to make a very energy efficient door.

The Present

Within the past few years, things have changed rapidly in the marketplace. Not only have advancements been made on all existing door products (wood, steel, fiberglass) but alternative composite products have been developed.

For example, one manufacturer, Marvin Windows, developed a wood veneer door that has a fiberglass composite core. This door offers a consumer an actual wood feel and appearance, but none of the problems associated with wood doors of the past. The fiberglass composite is dimensionally stable, like steel and fiberglass.

Another manufacturer, Therma-Tru, is also coming to market with a composite door. This door is supposed to be indistinguishable from a real red oak door.

Steel & Wood Changes

The steel door industry, in just the past few years, has responded to the steel look. Several manufacturers have developed thick (20 mil) vinyl finishes that have wood graining. This vinyl accepts stains available from the manufacturer. The end result is very realistic. Up close, it is hard to tell the difference between the steel door and a real wood door.

Certain steel doors also now feature improved insulation, extra reinforcing (for security) and significantly improved weatherstripping. Adjustable thresholds are available on many models.

Manufacturers of real wood doors have also improved their products. Doors made 100 years ago were often made from old growth timber that was extremely stable. The growth rings were usually very tight . However, these old growth reserves vanished within the past 50 to 75 years. As such, doors made within the past 50 years often had problems with increased swelling and twisting.

In response to this problem, manufacturers of real wood doors are using more stable laminated woodcores. Clear veneers of just about any species of wood are then applied over these laminated solid wood cores.

Some manufacturers go to great extremes to treat the doors with preservatives which inhibit any dimensional changes due to exposure to water or water vapor.

Closure

Never before have you, the consumer, had such a fantastic selection of door products. Just about any direction you head, you should be able to locate a quality product. Better yet, if you choose a non-wood product, there is a good chance that only you and your carpenter will know the truth!

Column B76

Entry Door Care Tips & Manufacturers

Steel, Fiberglass, Composite & Wood Entry Doors Manufacturers

The following is just a partial listing of entry door manufacturers. There are well over 100 that I could have listed! If a door company you are considering is not on the following list do not be discouraged.

  • Atrium Door & Window Company
  • JELD-WEN Windows & Doors
  • Eagle Window & Door, Inc.
  • Madawaska Doors, Inc.
  • Marvin Windows and Doors
  • Peachtree Doors and Windows
  • Pease Entry Systems
  • Pella Corporation
  • Taylor Building Products/Perma-Door
  • Simpson Door Company
  • The Stanley Works/Door Products Group
  • Therma-Tru Doors
  • Weather Shield Windows & Doors
  • Woodstone Architectural Windows & Doors

Door Care Tips/Literature

The newer doors often have very specific care instructions. There is not a catch-all program that will work for all doors. Because these doors represent a major investment in most cases, take the time to read the care instructions that come with the door.

This is very important with respect to finishing the doors. Some of the newer doors, such as the fiberglass doors, require very specific stains to achieve the best results. These stains are almost always available from the door manufacturer. If your contractor looks puzzled when you bring this to his/her attention, continue to probe.

The care of the newer steel doors that have vinyl finishes is important. The method of cleaning the door is important, as you might harm the vinyl if not careful. Once again, the doors come with specific care instructions, be sure to save this literature and read it.

After deciding upon which door you will choose, ask the supplier for specific care and installation instructions at that time. Read these things before talking to contractors. When interviewing contractors, ask questions to see how familiar they are with that particular door. See if they intend to do some (all) of the things that are required by the manufacturer. If you take the time to do this simple thing, I know you will rapidly find out who not to hire for your door job. I wish you good luck on your entry door project!

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Entry Door Installation Tips

Therma-Tru fiberglass door installedOrdering Entry Doors

Often people order doors with sidelights. Sidelights are decorative panels that fit on one or both sides of the door frame. Often these panels have glass in them. The problem with sidelights is this: Security. If a sidelight is attached next to the door frame where the door latch (lockset/handle) will be, the door will not be as strong as it could be. Order the door with a 2x4 or 2x6 stiffener between the side light and the door frame. This will allow you to install 2 1/2 inch screws in the striker plate assembly. With these screws it will be tough to kick in your door.

Try to purchase a door with an adjustable threshold. This is really important. Often, after installation (especially in new housing) lumber shrinkage causes the door to fit poorly. If this happens, air may leak under the door. Adjustable thresholds allow you to fix this problem easily.

Think about your lockset options before you order. Predrilled holes are available from just about all manufacturers. This could save you money when dealing with your carpenter.

Be sure to check on door frame options, especially if you intend to stain your door. Some doors offer stainable clear frames as an option. They might not be a standard feature!! Beware!

Installation

One of the most common mistakes I see is installing a new door right on top of the subfloor or slab. HUGE mistake!! If ever you have been in a newer home where the throw rug in front of the door is swept away each time the door opens, you know what I am talking about. The solution is simple: install all entry doors on top of a 3/4 inch piece of wood which is attached to the subfloor. In certain cases you may have to put in a one inch thick piece of wood. Be sure to account for this extra piece of wood in the rough-in dimensions when framing the house!!

Entry doors need to be shimmed with tapered shims when they are attached to the rough framing. The hinge side of the door has tremendous stress on it from the weight of the door. As such, after a door was right where I wanted it, I took out one of the hinge screws (one from each hinge) in the frame and replaced it with an identical screw that was 3 inches long. This screw would pass through the frame, shims, and into the rough framing. The stress from the door is now transferred to the framing, not the door frame.

The reveal (space between the door and frame when closed) should always be consistent when the door is installed correctly. If the reveal along the top or side tapers, something is wrong.

If installing a wood door, be sure to immediately read and follow the finishing instructions! You may lose your warranty if you dillydally around.

Column B76

Linear French Drain Illustration

! ! ! See Author's Notes at Bottom of Column ! ! !

Linear French Drain Illustrations


Author's Notes:

You may wonder if my advice is worth anything. Well, read what Jim Sanders wrote to me when he was at the end of his rope:

"Hi, I just wanted to write to give you the results of my "Trench Drain". I have had a wet crawlspace for 15 years. Water would fill the crawlspace at times, so we actually had to drill weep holes at the base so that it would enter the basement and eventually, the sump pump.

I have tried everything. Several contractors said that the only thing we could do was to bring the water into the house via drainage tile and let it enter the sump pump. That would work, but because I live on a 6' elevation, there is no reason that I should have water problems. It became like clockwork...when it rained, we would rush home from the lake or wherever we were vacationing so that we could be prepared to start the backup generator, in case the power failed. We even had our alarm company put a sump alarm on our system, so they could notify us if we had a power failure. Battery backup was not an option, because sometimes we lose power for days and during any rain, our sump would run every 7 minutes...just like clockwork.

I found your site and read the article on the trench or French drain. At first, it sounded a bit like "holistic healing" to me. I failed to understand why a 2 ft. deep trench, 4 ft. away from the house would do any good. How could this simple thing correct an extreme water problem that has plagued me for years, cracked my foundation, settled my garage floor and ruined almost every vacation?

The Linear French Drain trench running from the house. PHOTO CREDIT: Jim Sanders

The Linear French Drain trench running from the house. PHOTO CREDIT: Jim Sanders

I decided "what the heck". I had to dig by hand using a trenching spade and a pick-ax, because the builder back-filled our property with brick and blacktop. It took quite a bit of time. Because the ground level varies so much on that side of the house, I was not able to achieve exactly 2 ft. deep. It varied from 18" to 30" in spots, but the slope was downhill. The trench is about 80 ft. long. At times, I thought about filling it all in, because I just didn’t believe that it would work.

I stoned it, put tile in, and filled it with #1 round stone. I socked the pipe just for safety measure and I also used geotextile fabric on top, so I could cover with dirt and grass. I also ordered some clay and pitched from the house to the drain.

After a short rain, water is running away from the house. PHOTO CREDIT: Jim Sanders

After a short rain, water is running away from the house. PHOTO CREDIT: Jim Sanders

Result? For the last month, we have had 7 or 8 torrential rains, the worst of which was last night. It rained so hard, that our lawn washed out in spots because of the high clay content. Our sump pump, that normally ran every 7 minutes during and after rain, has not turned on for 4 weeks. The silt at the bottom of the sump well is now dry and cracking. Our crawlspace has not shown a trace of water or even moisture.

Since I couldn’t see correcting the foundation cracks or the garage floor settling and tilting until I corrected the problem's source, I waited to see if the trench drain worked first.

This week, I had a company come in and perform sort of a "mud-jacking" technique on the garage floor, which worked perfectly. Also, during the past few weeks, I parged the cracks in the foundation.

A dry sump pump. PHOTO CREDIT: Jim Sanders

A dry sump pump. PHOTO CREDIT: Jim Sanders

I just wanted you to know how this worked. I stressed for many years over this issue and the solution was nowhere near as difficult as I thought it would be.

As a side note, I went to the end of the drain tile during a hard rain to see what was happening. Water was running out of the drain tile in about the same exact volume that it previously ran out of the weep holes in my crawlspace. This winter will be interesting, because last year, the ground next to the house was so saturated that during a thaw, my sump would run constantly. I'm guessing that the ground between the trench and the house will probably be drier now going into this winter."

- Jim Sanders, Upstate area - New York

CLICK HERE to get FREE & FAST BIDS from local drainage expert contractors.

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Exterior Foundation Waterproofing Systems

Exterior Foundation Waterproofing Systems

The following companies make exterior foundation waterproofing compounds. Some are modified asphalts (Tuff n Dry) and some are rubber (Rubber Polymer Corporation.) I recommend that you call as many as possible and get product literature. Then discuss the systems with your builder. See what products he/she has had the best success with. Good luck on your project!

  • Certainteed Form-a-Drain
  • Grace Construction Products
  • Insulated Building Systems
  • Tuff-n-Dri Waterproofing
  • Wall Firma
  • Alco NVC 
  • Andek Corp 
  • Dow Chemical Co./Building Materials

Column B113

Soil Drainage Solution: French Drain Systems

french drain

In the center of this gravel is a linear french drain. Some call them trench drains as I dug a trench and put in a perforated pipe. This area never has standing water in it now. Copyright 2017 Tim Carter ALL RIGHTS RESERVED

! ! ! See Author's Notes at Bottom of Column ! ! !

French Drain Systems In The Soil Work

Last year, I did some consulting work for one of my readers here in Cincinnati. She had a massive drainage problem in her rear yard. Half of the neighborhood's water was flowing through and over the soil into her backyard.

Her basement was leaking, the yard was soggy, and she had flooding in heavy rains.

I designed a simple linear French drain system to solve the problem. After seeing my design and asking some questions, I got the feeling she wasn't convinced as to its ability to solve the problem.

I assured her it would work. She indicated that it had better as she intended to hand dig the system. I gave her a handy tip on digging trenches and even let her borrow my duckbill shovel. This tool and a handy square point spade are the only shovels to use when digging trenches.

Why A French Drain Works:

  • it captures water moving sideways through soil
  • water prefers to move through the pipe in the trench rather than the soil
  • surface tension SUCKS water from the soil into the trench drying out nearby soil
french drain pipe

Cross-section of a Linear French Drain including the all-important perforated french drain pipe. Copyright 2017 Tim Carter ALL RIGHTS RESERVED - Do NOT COPY this graphic.

Related Links

How a French Drain Works Video

Step-By-Step French Drain Install DVD

My French Drain Stopped the Water

Eight weeks ago, I received the most wonderful Thank You note in the mail. We had a somewhat wet winter with several periods of heavy rain.

My french drain system captured and diverted all of the surface and sub-surface water. Her basement was dry and the yard allowed you to walk in it without leaving a shoe behind! She mentioned in the note that water rushed from the outlet portion of the linear French drain like a fire hose. Needless to say, she was satisfied and most grateful.

French Drain Construction Methods

The woman who I am speaking of built the entire system without any help. I visited the job site to inspect the trench after the pipe was installed. She dug over 165 linear feet of trench by hand (working part-time) in 2 months. It was hard work, but she accomplished the task.

You can often do much of the work with a trenching machine. These handy devices can be rented at a tool rental shop and towed behind any car.

Most tool rental places will even deliver it to you. However, even with a trenching machine you still must do some work by hand.

The trencher does a majority, that is for sure! If you decide to use one, purchase a sheet of 4 x 8 1/2 inch plywood.

Rip the plywood in half lengthwise to yield two pieces 2 x 8 feet. The trencher discharges dirt to one side of the trench while digging. Place the plywood on the ground so the dirt piles up on it, not the bare grass.

It's a breeze to shovel the dirt from the plywood instead of the grass. Remove all loose dirt from the trench and tamp the bottom of the trench to compact the soil at the bottom.

Layout

If your trenching system requires different bends and turns to go around houses, sheds trees, whatever, then your layout is critical. If you do not dig the trenches properly, the pipe will not fit into the fittings that go around the bends.

I always dry fit my pipe and fittings together and lay them on top of the ground exactly as they will be installed. I then use a can of bright orange spray paint to paint the grass right next to the pipe. Always paint on both sides to make sure that you clearly mark the center of the trench. This layout will save you hours of extra digging!

Location of the French Drain Piping

If you want to dry out a leaking basement or a crawl space, then you must locate the linear French drain in such a way as to capture all or most of the sub-surface water that is flowing towards your house. If you have periods of flooding where surface water flows over your lawn, then the drainage system must extend to the surface to capture this water.

Linear French drains that are intended to stop water from entering a house work best if they're located approximately 4 - 6 feet away from the foundation. It's not necessary or recommended that they be placed closer to the house.

You want the piping in soil that was not disturbed during the construction of the house. Placing the piping too close to the house also concentrates water flow at the foundation!

The Effective Depth

Linear French drains do not need to be excessively deep to be effective. Remember, water movement through soils happens where there are air voids. In many soils, air is most plentiful in the upper 24 inches.

You want to install the piping system so that the pipe is level or has a slight downward slope to the discharge point. Do not install the pipe at a consistent 24-inch depth if your lot goes up and down. Doing this will trap water in the low spots of the pipe.

If your lot is rolling in nature, then you will have to use a builder's level or laser to make sure your piping is level or flows downslope. Do not underestimate the importance of this!

Use the Right Pipe

The pipe used to collect water from the soil must be perforated. Once collected and in transit to the discharge point, you can switch over to solid pipe. Only use perforated pipe in the areas to be drained.

I happen to prefer the PVC pipe that has two rows of holes in it. These holes must point down.

Pointing them up is not right. Do you think the water flowing through the gravel aims for and enters the holes? Wrong! Some water may go in the holes but the majority goes past it and simply saturates the soil until the trench fills with water to the height of the holes.

Gravel Fill

Once you have placed the pipe in the trench, fill around the pipe with 1-inch washed gravel to within 1 or 2 inches of the surface. The best gravel is about the size and shape of a large grape.

Cover the gravel with a piece of sod. Do not place any dirt in the trench. Water traveling through the soil will find this gravel and immediately fall down to the pipe. The large voids around the 1-inch gravel will accommodate a rapid flow of water.

If you have to bring the trench system to the surface to capture surface water, dig out soil to make a path. Use colored gravel for the path placed around fieldstone or stepping stones. It will make a unique attraction and landscaping feature in your yard.


Author's Notes:

You may wonder if my advice is worth anything. Well, read what Jim Sanders wrote to me when he was at the end of his rope:

"Hi, I just wanted to write to give you the results of my "Trench Drain". I have had a wet crawlspace for 15 years. Water would fill the crawlspace at times, so we actually had to drill weep holes at the base so that it would enter the basement and eventually, the sump pump.

have tried everything. Several contractors said that the only thing we could do was to bring the water into the house via drainage tile and let it enter the sump pump. That would work, but because I live on a 6' elevation, there is no reason that I should have water problems. It became like clockwork...when it rained, we would rush home from the lake or wherever we were vacationing so that we could be prepared to start the backup generator, in case the power failed. We even had our alarm company put a sump alarm on our system, so they could notify us if we had a power failure. Battery backup was not an option, because sometimes we lose power for days and during any rain, our sump would run every 7 minutes...just like clockwork.

I found your site and read the article on the trench or French drain. At first, it sounded a bit like "holistic healing" to me. I failed to understand why a 2 ft. deep trench, 4 ft. away from the house would do any good. How could this simple thing correct an extreme water problem that has plagued me for years, cracked my foundation, settled my garage floor and ruined almost every vacation?

The Linear French Drain trench running from the house. PHOTO CREDIT: Jim Sanders

The Linear French Drain trench running from the house. PHOTO CREDIT: Jim Sanders

I decided "what the heck". I had to dig by hand using a trenching spade and a pick-ax, because the builder back-filled our property with brick and blacktop. It took quite a bit of time. Because the ground level varies so much on that side of the house, I was not able to achieve exactly 2 ft. deep. It varied from 18" to 30" in spots, but the slope was downhill. The trench is about 80 ft. long. At times, I thought about filling it all in, because I just didn’t believe that it would work.

I stoned it, put tile in, and filled it with #1 round stone. I socked the pipe just for safety measure and I also used geotextile fabric on top, so I could cover with dirt and grass. I also ordered some clay and pitched from the house to the drain.

After a short rain, water is running away from the house. PHOTO CREDIT: Jim Sanders

After a short rain, water is running away from the house. PHOTO CREDIT: Jim Sanders

Result? For the last month, we have had 7 or 8 torrential rains, the worst of which was last night. It rained so hard, that our lawn washed out in spots because of the high clay content. Our sump pump, that normally ran every 7 minutes during and after rain, has not turned on for 4 weeks. The silt at the bottom of the sump well is now dry and cracking. Our crawlspace has not shown a trace of water or even moisture.

Since I couldn’t see correcting the foundation cracks or the garage floor settling and tilting until I corrected the problem's source, I waited to see if the trench drain worked first.

This week, I had a company come in and perform sort of a "mud-jacking" technique on the garage floor, which worked perfectly. Also, during the past few weeks, I parged the cracks in the foundation.

A dry sump pump. PHOTO CREDIT: Jim Sanders

A dry sump pump. PHOTO CREDIT: Jim Sanders

I just wanted you to know how this worked. I stressed for many years over this issue and the solution was nowhere near as difficult as I thought it would be.

As a side note, I went to the end of the drain tile during a hard rain to see what was happening. Water was running out of the drain tile in about the same exact volume that it previously ran out of the weep holes in my crawlspace. This winter will be interesting, because last year, the ground next to the house was so saturated that during a thaw, my sump would run constantly. I'm guessing that the ground between the trench and the house will probably be drier now going into this winter."

- Jim Sanders, Upstate area - New York

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