starter strip

i guess this might be considered a double posting, but i first had this question listed in the "do it yourself" forum and didn't get any responses.


"i've installed five vinyl windows and each came with a "starter strip". i've had problems with each of them staying in the channel while placing the window into the frame.

since the windows fit very well both horizontally and vertically my question is whether the starter strip is really needed?"

Do you mean sill expander? Does it go between the bottom of the window and the sill? What brand window?

Ronnath,
I am assuming you are speaking of the L shaped sill angle. It is used for window sills with a slope.
That piece gets nailed to the sill, and then when you put the window in it slides in over the top, making sure the window is out further than the angle.

Many pros use their metal bending skills to do away with the angle by custom bending a couple extra bends in their sill piece to fit up tight under the window.
Some brands have snap-in sill pieces that you cut and hammer on afterwards.

roofingun: just checked the instruction sheet - they call it a "sill adapter". yes, it goes across between the bottom of the window and the sill. the windows are "Thermastar by Pella." In another post i saw someone said these used to be called "Viking" before Pella bought them out.

Window4u: yeah, it's an "L" shaped piece

Ronnath - The sill expander piece you have can go on like W4U stated. It can also be applied to a groove on the bottom side of the window. The piece usually comes with scoring down one side so you can trim it to the correct depth. Then as your tilting the window in place it slides up the groove from the bottom. Your suppose to caulk under the bottom side to seal it to the sill. We find installing it after the window is inserted and insulated a bit harder. It's just easier to insulate and get everything in place before attaching the expander strip. You have to cut it just right in order to fit. We only use them in odd applications. Otherwise we do as W4U does and brake metal to take up the gap.

It's a sill expander. It expands the sill.