windows

i finished putting in the windows yesterday. i was also very sore and tired for some reason, so i slept in today. i was going to put up the remaining shingles on the front roof today, but we're going to have heavy rain and winds in the next few days, and i don't want to subject new shingles to high winds.

so i'm deciding what to do instead. while i'm here, i might as well update my blog thing. since i've neglected it for quite some time. february was the month of doing nothing it seems. between crazy weather, sickness, and general lack of motivation, i accomplished little..

anyway, let's discuss the windows. they are pella impervia, fiberglass composite windows. this material expands at a rate nearly identical to glass, so as temperatures fluctuate due to seasons and solar exposure, the seals between the glass and frame should remain under consistent pressure and ideally will last much longer than a window of any other type.

all of the windows are either casement, awning, or fixed. no hung/slider types. the operating windows utilize a compression-type seal, which ensures maximal air tightness. sliding-type windows tend to achieve less tightness. (good little factoid on window air tightness)

i spent some time deciding on how to flash the windows. there are many options, and i liked some details i found online in an ASTM article. it describes construction of a SAF (self-adhered flashing) sill pan. SAF are asphalt/butyl-based tapes that are supposed to stick forever and keep out water - also called 'flashing tapes.' a sill pan is located at the bottom of a window, where it has a lip toward the inside which diverts water back toward the exterior. you can see the lip well in this shot:

From vinnie pics by mike

because of how the sill pan fills three-dimensional space, it can't be constructed with a single sheet material, but has to be built-up. i've got some pics of the sill pan construction:

From vinnie pics by mike

From vinnie pics by mike

From vinnie pics by mike

From vinnie pics by mike

From vinnie pics by mike

and wala, sill pan installed. cutting the pieces takes longer than installing them. after the sill pan goes on, then felt jamb flashing is attached (you can see it in place in the first shot above.) then the window goes in and i strap a piece of OSB across it to hold it temporarily in place.

next i go inside and direct a vertical laser beam along an edge of the window. i carefully insert shims at the manufacturer-directed locations at the top and bottom jamb locations until the window edge aligns with the laser on both left and right edges. i check both edges to be sure.

then i return outside and nail up a ton of roofing nails into the fins of the window. i kept nails out of the bottom nailing fin, as these are a prime location for water to find its way into the wall, and i feel (after running some structural calcs) that there are sufficient nails to keep the window secured in position. only the awning windows and the wide fixed windows had a few nails placed in the bottom fin.

tada, window installed. lookin good:

From vinnie pics by mike