How to Install Aluminum Windows

Preparation is the key so make sure the rough opening is as close to perfect as possible. If you're up for the installation, there are options, and this set of instructions follows the AAMA Method B recommendations using the drainage option.

How to Install Aluminum Windows in Well-Defined Steps

1. Make sure the rough opening is clean and perfectly balanced. Measure it carefully and see to it that the window assembly leaves 1/2" along the top and sides with 3/4" clearance at the bottom because of the drainage-enabled installation. Also check the window assembly for dents, bends, and any imperfections

2. Add double 9"-12" flashing along the bottom to provide a waterproof bed to handle drainage.

3. Add flashing around the rest of the opening. Special plastic flashing corners can help maintain things level and plumb.

4. Add a 1/2" sealant bead around the entire nail fin on the window leaving two 2" gaps at the bottom 3" from each lower corner. Insert the window assembly into the opening and press firmly until sealant squeezes out from wherever it was applied. The gaps show the drainage openings.

5. Put in a limited number of screws and use a carpenter's level to make the window level and plumb. When properly positioned, affix the rest of the screws.

6. Add special chevrons to seal any open channels in the aluminum frame. Then add another bead of sealant around the entire assembly and butter it flat covering all fasteners.

7. Add final flashing at top.

8. Add sealant at the lower portion on the inside to weatherproof the installation.