A step-by-step DIY tutorial on how to install window jamb extensions, the perfect way to update your home.
We are making some progress on our windows. We finally got all the tile removed from the window sill, it is a happy day! But the next part of the project is what we have been worrying about from day one. Why? Well, our windows are framed around brick and plaster and getting anything to hold/stay does not work very well. For example, all the blinds that were installed in the house, the screws that were holding them up basically fell out when we took the blinds down. So we were worried about trying to get a wood frame to stay in place. But good news, that was not a problem… And here is how to install window jambs extension, even if the wood is not surrounding your windows.
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And because I am all about sharing what we started with, here are our windows before.
After removing the tile from our windows, we had a big gap where the mortar was, see how we have brick surrounding the window…
To fix this problem, we added a 2 x 6 board.
NOTE about CUTTING BOARDS: To cut the boards, we measure first. We measured right next to the window then the length next to the wall because sometimes they are different sizes. Then we cut and tested them to make sure they were going to fit.
One of our best friends during the whole process was liquid nails. To say the least, this stuff is amazing… We applied the liquid nails to the brick to hold the board in place. We also added shims to make sure the board was level.
We also added a 1/2″ x 4″ boards to the top of the window to fill in the gap at the top (We had lots of gaps…). To do this we added liquid nails to each piece of wood then taped the wood to the wall. We then let it all sit for 24 hours to dry. Do you love the old sheet as our curtains? With tape holding it to the wall, we are high class in this house…
HOW TO INSTALL WINDOW JAMBS EXTENSION
Then we started on the jamb extensions. We used 1 x 6 boards cut to the width of the window (which was cut down to 5 1/4″ to 5″ “x” the length of the window). After making sure the window sill (bottom board) was going to fit. We then applied liquid nails to the base of the window.
TIP: Make sure all the boards fit before adding the liquid nails. (I know I have said this twice but it’s really important…)
Then we added the new window sill.
Make sure the sill is flush with the wall.
You can have a little gap between the window and the board, you will fill this in with caulk.
Then we nailed the board into place with 2″ nails.
The next couple of steps there are no pictures because we needed both of us to complete the steps. But I will explain what we did but it is the same process as the window sill step (last step).
First, we added the board that would be placed at the top of the window jamb then moved to the sides. And again make sure you test your boards first to make sure they will fit.
To add the top board/jamb, we applied liquid nails to where the little 1/2″ board then nailed the 1 x 6 board to the 1/2″ boards. We then added liquid nails to the side boards and nailed them into place. The finished window looked like this…
Before installing the window jambs and after, I did apply window foam to the gaps to insulate around the windows.
It is amazing how quiet our windows are now that we have added the jambs (we could hear cars driving up and down the road before). I cannot wait to get the trim added to the windows. BUT then I have lots of painting ahead of me…
The only problem we encountered during the step was the boards… Problem 1: We bought the cheap pine board and had them for about 3 weeks before getting to this step and during that time the boards warped, so lesson learned buy boards and complete project within a couple of days.
Problem 2: We got the width cut at the hardware store and some were not at the right width, so we have some bigger gaps but the caulk will fix that. We were really wishing we owned a table saw instead of having to find someone with one, we really like this table saw.
Anyone thinking about giving their windows a makeover? Have you thought about the window jamb extension?