How to Build Glass Room Additions

Glass room additions are a wonderful way of expanding your home’s square footage while at the same time providing you with the indoor and outdoor experience such additions offer. It is interesting to note that the actually hands-on building process is quick and simple while the planning session takes a good bit of time and effort. Follow these steps and you will be well on your way to learning how to build glass room additions that will add value to your home and increase your quality of living on a daily basis.

How to Build Glass Room Additions—Planning

Build Glass Room Additions
  1. Acquire extensive knowledge of local building codes, as the building department will require your room addition to fulfill all the laws with respect to framing in order to recognize them as a bona fide square footage addition. Fulfilling this requirement is going to increase the value of your home but also possibly your tax liability. Use the Internet to contact your local building department and get up to speed on all the rules and limitations.

  2. Search for a reliable retailer who will sell you low-emissivity glass and precut the panes for you according to your specifications. Not only will this decrease the amount of time spent trying to make commercially available panes fit, but it also eliminates the error margin, thus decreasing the cost. Low-emissivity glass is usually referred to as “low-e” in the trade. The Internet is a great source of finding such retailers.

  3. Measure the area where you want to build the glass room additions. Draw an outline with your pencil on the notepad. Use the ruler to make sure you are drawing the blueprint to scale!

  4. Take a close look at the surrounding area and decide on drainage. A French drain might be the easiest way to accomplish this feat if you receive average rainfall throughout the year. You need to add about eight to nine inches to the width of your addition circumference for the drain. Make sure to memorialize that on your notepad.

  5. Understand the weight distribution the roof of your glass room additions need to carry. The easy way is to simply roof them as normal room additions, but if you have your heart set on glass, you must remember that areas where snow is a winter reality can find quite a bit of weight piled onto the glass panes. Contacting a builder or discussing the options with your building department will send you in the right direction.

  6. Visit your building department and have the final blueprint approved. This is a crucial step and should not be overlooked!

How to Build Glass Room Additions—Executing

  1. Frame your glass room additions following the specifications of the building department. Invite the home inspector to come out and inspect your finished frame to avoid any future surprises.

  2. Install precut low-e glass panes, following the manufacturer’s recommendations carefully with respect to adhesion.

  3. Apply neoprene weather stripping to the inside and the outside of the windows.

  4. Fill in the framed portion that will not contain glass with the material of your choice. On the inside, cover it with precut tongue in groove wood slats that reflect the color and grain scheme of other exposed wood in your home.

  5. Seal the wood with UV repellant polyurethane sealer. Even though low-e glass is sure to virtually eliminate the harmful rays of the sun, the sealer will pick up the slack and ensure that the wood’s color will not fade.

  6. Add the roof to your glass room additions.

  7. Install the flashing all around the area where the glass room additions connect to the house.

  8. Invite the building inspector to come out again and have your finished structure inspected. Since you have worked out the details of the structure in the planning process outlined in Section 1, this should only be a formality.


  • Glass room additions will leak. There is virtually no way to prevent this.
  • Forgetting the flashing is a common and costly oversight you must avoid.

About the Author

Based in the Los Angeles area, Sylvia Cochran is a seasoned freelance writer focusing on home and garden, travel and parenting articles. Her work has appeared in "Families Online Magazine" and assorted print and Internet publications.