Leak-Free Skylight Installation Tips

Understanding Flashings

As I address in another article, a wide majority of roof leaks occur where 'things' stick up through roofs. Shingles in and of themselves rarely leak, except when worn or damaged by wind. Flashings are almost always the first place I look when a leak has developed in a roof.

Skylight technology has advanced to a point where the skylight itself is virtually leakproof. The only way a leak will develop is where the roof butts up against the skylight. This, of course, is where the flashing is!

Most roofing materials such as shingles, slate, tile and cedar shakes depend upon gravity to keep water from entering your house. The roofing materials generally overlap one another in a staggered fashion to shed water down the roof. The steeper the pitch of the roof, the better the system works. Low pitched roofs are more prone to developing leaks because the water moves down the roof at a slower rate.

Flashings work using the same principles. They overlap one another beginning at the bottom of the object where it penetrates the roof. Each course of roofing material has a piece of flashing (step flashing) on top of the last piece of roofing which abuts the object which is penetrating the roof. The next (higher) course of roofing materials then covers this flashing. The flashings are 'laced' into each course of shingles, slate, etc.

The only way that water can enter alongside the 'object' is for it to travel uphill (against the force of gravity). This phenomena can happen in areas that receive snowfall. They are called ice dams. If you live in such an area, special products need to be included in your skylight installation to prevent leaks from ice dams. This linked article talks about these special products.

If you decide to hire an individual or company to install a skylight for you, ask them pointed questions about flashings. If you don't know the questions to ask, read up on flashings. Most of the skylight manufacturers have helpful literature explaining their individual flashing kits or systems.

Following Directions

I have installed many different brands of skylights. While all are similar, there are specific steps involved with each skylight in order to ensure a leak-free installation. It is important for you to make sure that you and your installer read the instructions before proceeding.

This is especially true if you are installing a skylight which opens and closes. Examples of this are 'ventilating' skylights or roof windows. The installation of these units is very critical. If directions are not closely followed, there is a good chance that the skylight will bind or close improperly. If this happens, be prepared for a leak!!

Caulk and Roofing Cement

Caulking and roofing cement are materials that generally should not be found on your jobsite. Some installation instructions call out for sealants to be used in hidden locations as an extra precaution or insurance policy against leaks. These materials should never be used in exposed areas of the skylight installation or alongside the frame or flashings. If these materials are used in this fashion on your skylight, something is wrong!

Caulking and roofing cement work well for emergency or temporary repairs. They are not to be used as permanent solutions to a leak. Don't let someone tell you differently.

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Brrrrrrrrr! Can you feel that draft through those older double hung wood windows? Are you tired of cleaning those aluminum triple track storm windows that have pitted and oxidized? Would you like new wood windows with top of the line Low-E glass, but you don't want to change the architectural integrity of your house? If so, you are a prime candidate for wood window replacement kits.

Rattle, Rattle

Do your existing wood double hung windows rattle in their frames? I mean even slightly? Have you noticed that outside noise is very pronounced when you stand close to these windows? Have you ever seen any weatherstripping on these windows? I already know the answers to these questions.

Old fashioned double hung wood windows leak HUGE volumes of air. They never had any weatherstripping installed at the factory. Heck, I don't even think they had weatherstripping 70 years ago! A really good indicator of the amount of air that these windows leak is the amount of noise you hear through them. Sound waves travel through air. Air travels between old wood windows and the window jambs.

Free & Fast BIDS

CLICK HERE to get FREE & FAST BIDS from local replacement window companies that can install these awesome kits.

If you block all air passages into a space, noise can only be created by actually vibrating the walls or floor. You can demonstrate this by touring a new model home. Most of these houses are quite air tight and as such, they are eerily quiet inside. Wood window replacement kits can go a long way in duplicating this effect in your home.

On the Ropes

Have you ever had to replace a window rope or sash cord? If you accomplished this task successfully, you can install virtually any of the window replacement kits by yourself.

I have personally installed hundreds of these windows. They are a breeze to install. Granted, the first time I installed one I was scratching my head for a while. But, once the window popped into place, BINGO! On average, it only took me about an hour to install a window from start to finish.

These kits are attractive for several reasons: the complete installation can happen inside the house (no need for ladders), the exterior and interior woodwork escapes the process virtually untouched, most kits provide you with an exterior full length screen, virtually every window is either removable or tilts in for easy cleaning and maintenance.

How is it Done?

Your double hung windows can be removed in a flash. Remember that narrow (1/2 x 1 1/4 inch) piece of stop molding that holds the lower window in place? That and the parting stop (narrow 1/2 x 3/4 inch piece of wood that separates the two windows from one another) are the only pieces of wood that stand in your way. Remove these pieces of wood and the sashes (windows) flop around in the opening like fish on a pier.

Now the only thing holding the window in place is the sash cord. I always cut these and let the window weights drop inside the frame. The last items to remove are the two window pulleys. After a little practice, you should be able to accomplish the entire removal in just under 15 minutes.

CLICK HERE to get FREE & FAST BIDS from local replacement window companies that can install these awesome kits.

Look Mom, no Weights!

These newer windows operate by using spring loaded balances that are hidden in thin jamb liners. The jamb liners fit on the sides of the window frame. Usually they have a foam backing which acts as an insulator, a wind break and provides the flexibility required to allow you to install and remove the sashes in just seconds.

Quality manufacturers make these jamb liners out of long lasting maintenance free vinyl. They attach to the sides of the window opening with metal clips that are simply nailed or screwed to the frame.

Hidden within the jamb liners are spring balances that allow the windows to glide up and down with minimal effort. The liners have a contour to match each sash. This provides for an airtight fit along the sides of the window.

Options Galore

Have you been to a new home lately? How about a window showroom? If so, you probably have seen the multitude of options on new wood windows. Well guess what? Virtually every option you have seen in complete windows is available in the wood window replacement kits. After all, the major components of a new window are the sashes, the glazing (glass), the jambs, grilles and interior and exterior finishes. Well, when you purchase a kit, you get all of these things. Remember, the only distinction between these kits and a full window is simply the frame.

One manufacturer, Weather Shield, offers many different species of wood, including traditional pine, oak and cherry. This option could come in very handy if you are attempting to match windows in an existing study or library. It may save trying to "grain" a pine window to match.

Another manufacturer, Pella, offers an unusual kit. They actually supply a thin frame which evidently fits into the opening you create after the old windows are removed. My guess is that this kit possibly reduces the daylight opening of the completed window.

The kits that do not offer the extra frame rarely, if ever, reduce the actual glass area or daylight opening.

My personal experience has primarily been with the Marvin Tilt-Pac. Marvin goes to great lengths, as do many manufacturers, to produce a window sash that matches architecturally. You can even order the windows with the curved horns that often appear on the top corners of many older bottom sashes. This is a very fine touch.

If you are looking for a maintenance free exterior, several of the manufacturers offer aluminum clad exteriors. However, prior to ordering this option, be sure that your existing openings are very square. For a perfect fit, the sashes often need to be scribed. Aluminum doesn't react favorably with a belt sander!

Measuring the Opening

If you decide to tackle this project yourself, I suggest getting some assistance from the local distributor when measuring. Remember, these windows will be custom made to fit your opening. There is no taking them back if they don't fit. Mistakes are costly! Check and re-check your measurements. If you measure accurately and have a square opening, you will be able to crank out a window an hour. Good luck!

CLICK HERE to get FREE & FAST BIDS from local replacement window companies that can install these awesome kits.

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Wood Windows - Replacement Kits Manufacturers

The following manufacturers make the kits you are looking for. Check out the web sites to get a full description of the products they offer. All of them have step-by-step instructional literature that shows you exactly how to install the windows. Yes, I know, it isn't the same as doing it, but it can be a big help. I am sure in this day and age, they now have instructional videos.

There is a good chance some of these instructional pieces will forget to show some important steps. There are very few pitfalls. The secret is obtaining accurate measurements and checking the opening for square.

One major benefit to this type of project is that you can simply order one window. This way, you can determine how tough the project will be. If you succeed installing the first window, which you most likely will, you can place a follow-up order to complete the job. Be sure to find a dealer close to you.

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Block windows have really created lots of consumer interest in the past 20 years. I actually remodeled the office and fabrication shop space when the first glass block company moved into the Cincinnati, OH market. I was astonished by the precision laying framework that was used to make the individual sized panels. At the time, I thought it would be a passing fad. Good thing I didn't bet on that!

A Commercial Product

Glass blocks have been around for nearly 80 years. They are a classic art deco building material. Block windows also were in vogue in the 1950's and 60's as well. Fifteen years ago, things really got interesting.

The block windows were originally used in commercial and industrial applications. Frank Lloyd Wright used them in a house located only 3/4 of a mile from my house. I guess if he can use them in a house, it is OK!

Whatever the reason, millions of them are being used around the world in residential construction every year. They are practical in many applications. You can even purchase clear block windows that pivot and open just like any old casement window. That opens up all sorts of possibilities......no pun intended.

Installation Skills Vary

Complicated installations of glass block require skills of a master mason. Large block panels require horizontal wire reinforcing. Special hidden anchors are used on the sides of the block as they are laid.

Things are a little different if you choose to use a lightweight clear acrylic block. These block are available in large panels that come assembled from the factory. They weigh much less than traditional glass block.

Windows less than 6 square feet in size can be tackled by an average homeowner. This is because fabricators have sprung up in all corners of the nation. These people pre-make the windows for you. You simply install one large panel.

The pre-made panels are also available at many home center stores. Just one month ago, a friend of mine purchased two to install in a rehab job. He walked right in and BINGO, there were the right sized windows. It couldn't have gone smoother if you tried.

Caulking Method

The maker of the glass blocks has developed a method that allows you to install glass block piece by piece using vertical and horizontal spacer strips and clear silicone caulk. I haven't tried this method. If you try it, I suggest that you have plenty of lacquer thinner on hand to remove silicone caulk smears.

Excellent Literature / Videos

Because of the widespread popularity, the block window manufacturers have created many helpful pamphlets, booklets and videos to help you design and complete your glass block window projects. All you have to do is call them and order these materials. It is also quite possible that these materials are available at local distributors.

Pricing Varies

I received a phone call from a Michigan reader. He informed me that he can get an average basement block window installed (all labor and materials) for less than $50 per window! That is a superb deal. The price here in Cincinnati is almost twice that. I guess there is a savage price war happening in Michigan!

When you are shopping, be sure that you are comparing blocks that are the same thickness. Ask for copies of both Worker's Compensation Certificates and General Liability Insurance. Low price installers generally work without these important policies!

If you decide to have a company install your windows, do not pay more than 25 percent as a down payment. Your state law may even permit you to pay less. Beware of individuals who demand 50 percent or more.

Energy Efficiency

The block windows that do not open offer great energy savings. The reason lies in the fact that they can reduce air infiltration to zero. Many old basement windows were poorly weather stripped.

If you do intend to install these windows in your basement and you have gas (or oil) furnaces and water heaters, PLEASE have the fabricators install a 4 inch piece of PVC pipe in the window(s) closest to the equipment. This will allow you to run a combustion air pipe to the appliances.

Remember, these devices need massive amounts of fresh air when they are burning. Your new windows will rob these appliances of their air supply unless you provide the opening. This feature will cost less than $10 per window on average.

Custom Shower Bases

Do you want a glass block shower stall? It couldn't be easier! Pittsburgh Corning makes three different styles and my favorite is the walk in shower. It requires no shower door because of a 90 degree curved wall that captures the water spray. It is so cool! The acrylic bases come in seven colors to boot. They are made to support the weight of the glass block so there is no fear of fracture over time. The built-in flashings are also a swell feature.

Author's Note: We've received other questions with similar problems or questions. Here's one from Lena K. of Rockville, MD, regarding basement replacement windows.

"Our basement windows leak air as well as water when snow melts. The house was built in 1965 and the windows seem to be from that time. They are below the ground level with wells dug out around them. They are set directly into concrete blocks. I looked at different replacement window manufactures and installers, and none of the ones I saw offer specific windows for basements. Do you have any suggestions? (We aren't planning on doing the replacement ourselves). Thank you."

Companion Articles:  Glass & Acrylic Blocks Do Many Things, Glass Block Installation, Glass Block Manufacturers, Glass Block Greenhouse

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Glass Block Manufacturers

Talk about your David and Goliath comparisons ... here we have a classic. There is only one manufacturer of true glass block that I know of. It is Pittsburgh Corning Corporation. The only other manufacturer makes a similar product, but not from glass. They make a block from clear acrylic plastic.

The two products look identical, but there is a vast difference in weight. The glass blocks are much heavier than the acrylic blocks. You will discover a vast amount of different sizes and patterns with both types of block.

Both systems have positives and negatives. I urge you to visit both of the websites of these companies. They have excellent information. Find and visit the local distributor in your area and take a look at all of the wonderful samples. Information on the web will give you a good head start, but wait till you actually hold some of the different blocks in your hands.

I also urge you to talk with the salespeople about the real challenges that glass block pose. They are not that easy to install, I don't care what anyone tells you! This is especially true if you are laying real glass with mortar. When you lay brick, the dry brick has a certain amount of suction that pulls the water from the wet mortar. This allows the wall to get stiff as you install the brick. Glass has zero suction! If the mortar is too wet, the blocks below that you just laid start to swim and move all over the place. You can only lay so many and you have to stop and wait for the mortar to set up. Still want to try? Then do a very small panel to start with.

• Hy-Lite Block Windows
  These guys make the 100 percent acrylic block.

• Pittsburgh Corning Corporation
  This is the place for "glass" block! The originators!

Companion Articles:  Glass & Acrylic Blocks Do Many Things, Glass Block Installation, Glass Block, Glass Block Greenhouse

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Glass Block Window Design Suggestions and a Funny Story

Do you have a window on the side of your house that faces a neighbors house? Do you feel like a fish in a bowl? Why not replace that window with wavy glass block? You can throw away the window shade and curtain! Abundant light will shine in, but your neighbor's watchful gaze will be permanently blocked.

How would you like to build a contemporary wet bar? Why not use glass block as the base for the bar? Backlight it with colored light bulbs for a dynamic look.

What about that dark spot between your kitchen countertop and the wall cabinets? You can brighten it with block windows!

Room partitions can be built using block windows. They allow natural light to travel uninterrupted from room to room. Mix and match block designs within the same wall for an interesting look.

As crazy as it sounds, how about block panels as the balustrade in a stairwell? You can build staggered wood boxes that will accept the panels between the handrail and the stairs.

Shower and tub enclosures are great places for block windows.

Don't let corners or angles stop you! Outside corners, endblocks, 45 degree blocks and hexagonal blocks are all available.

You may enjoy this story. A few years ago, I built a very interesting room addition on top of a structural-steel frame. This room addition was similar to a deck and it extended over a driveway apron for a three-car garage. The structural-steel frame was needed to support the weight of the addition.

The addition was really a giant master bathroom. The architect had selected a wavy glass block for a large full-length window in the shower stall. This glass-block window faced the woods behind the house.

One day while I was installing the tile, the wife stopped by to check on the job progress. Not only were we building a room addition, but we were also rehabbing about 90 percent of the entire house. It was impractical to live in the house while the work progressed.

This woman had a marvelous sense of humor as I had discovered while working on the job. While I was inside the shower area working on the tile she remarked, "Wow, the glass-block window sure let's in lots of light!" I agreed and replied, "Oh yes it does. By the way, who selected the glass pattern?"

This glass block was smooth glass, but the thickness varied so when you looked through it things were really fuzzy and distorted.

She replied, "Oh, the architect did. My husband and I thought it would really match the 1950's style of the home."

I responded, "Well, we love it when the architect specifies this glass block." She said, "Why?"

Keeping a perfectly straight face, I said, "This is a unique glass block. When you stand close to it and look through it, things are fuzzy. But when you stand back, like in your woods, it acts like a magnifying glass. I wonder if the manufacturer has ever realized that?"

Her jaw dropped and eyes widened as she no doubt was thinking about the peep show she was going to offer to any and all who happened to be looking at the addition while she showered. I let her astonishment bake for about a minute or so and then said, "Gosh Carol, I was just kidding!"

She got very embarrassed because I fooled her. We remain friends to this day. Her house is only two away from mine!

Author's Note: We've received other questions with similar problems or questions. Here's one from Lena K. of Rockville, MD, regarding basement replacement windows.

"Our basement windows leak air as well as water when snow melts. The house was built in 1965 and the windows seem to be from that time. They are below the ground level with wells dug out around them. They are set directly into concrete blocks. I looked at different replacement window manufactures and installers, and none of the ones I saw offer specific windows for basements. Do you have any suggestions? (We aren't planning on doing the replacement ourselves). Thank you."

Companion Articles:  Glass & Acrylic Blocks Do Many Things, Glass Block Installation, Glass Block, Glass Block Manufacturers, Glass Block Greenhouse

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HI TIM! My husband and I built a home about two years ago and requested Low-E glass for all of the windows in our house. We mainly were trying to protect our hardwood floors and our furniture from fading. It hasn't helped, AT ALL. My curtains, dining chairs, living chairs, etc. have all faded considerably. I have reason to believe that my windows may not actually be Low-E (which we paid for) and wondered if there is any way to distinguish. Sincerely, Michele Sells

DEAR MICHELE: Low-E glass is not supposed to block ultraviolet (UV) rays of the sun which are responsible for your color-fade problems. Low-E glass does a fantastic job of blocking heat using a thin metallic coating on the inside surface of insulated-glass panels. To protect the possessions inside your home, you should have covered the windows with a window film that does stop UV radiation.

Window films are plastic sheets of varying thickness that perform many functions. Some window films stop UV rays, some stop infrared (IR) rays which cause things to heat up inside your home on a summer day. If you have ever walked in front of a window where the sun is streaming in, you can instantly feel the IR radiation on your skin. Other window films do double or triple duty. Some thicker window films will block UV, IR and large objects from coming into your home. These thicker window films are used to stop windows from being blown out during hurricanes or other large windstorms.

You can often see the ultra-thin metallic coating of Low-E if you look at clean windows on a sunny day at an approximate 30 degree angle. The glass will often appear to have a bluish or even light green cast to it. Regular glass that has no Low-E coating never has this coloration.

You may have to look at your windows at different times of the day to detect this coloration. It is not readily apparent. It may pay to go to a hardware store to buy a piece of regular glass to help you determine if you have Low-E glass. If you have someone hold the regular glass next to your windows and ensure the glass is parallel and in the same plane as the window glass, you might see that the regular glass looks very different than your windows.