hi everyone,
I was hoping for some advice on fastening windows with stain grade vg fir jambs into wood framing. Are 15 guage finish nails sufficient and if so, any recomendations on spacing? Should i be drilling for screws and plugging and if so, any recomendations on spacing and blending the finish on the plugs to the pre-finished jambs?
The housewrap/window flashing detail is signed off on and my plan was to use backer rod and caulk on the outside to seal to the window opening with low expanding foam in the cavity. Does the foam/caulk provide enough adhesion to make 15ga nails enough?
thanks in advance.
db
Replies
what is the context
rough opening to new jambs? good shims, spacing etc.?
interior & exterior casing?
this is new 2x6 construction with new windows and will have a rainscreen system over the housewrap as it's on the coast of BC. window jambs are fir approx 1 1/2" thick and i believe i've undersized the windows by 3/4" in width and 1" in height to the rough opening (don't have my notes here...). Shims could be whatever is best practice but i was planning on the plastic horseshoe shaped shims on the sill and the tapered composite guys on the sides. The current plan is to have the casings lap onto the jamb with 1/4" reveal but exact finish is not yet confirmed. interior and exterior casings would be stain grade fir. There could be flexibility here in style if there is an advantage for hiding fasteners holding the window, although i can't think of what that would be...Hope i'm answering your questions.db
I'd have to say that 15ga nails are nowhere near strong enough (on their own) to keep a window in place. Especially an operable window or anything of significant size. I'm not saying it hasn't been done, it's that I would never do it.
Is the exterior casing factory installed, or are you installing on site? Any recommendations in the manufacturer's instructions? One option would be masonry clips or straps. They're attached to the rough framing side of the window frame and are pulled in and secured to the rough opening on the inside.
thanks, i figured the 15ga weren't sufficient. i'm trying to avoid drilling for screws and plugging becuase it would seem impossible to nicely blend the finish on the plugs into the factory finish. i like the idea of the brick ties - thanks. any other ways to go about it?the casings will be installed on site.db
The normal way for wood windows to be installed is to fasten thru the ext. casings once they are attached to the window frame. I've started using SS trim screws thru the casings to hold the window in place on the rare occasion someone wants a real wood window. The small hole left by the screwhead is easy to fill.
We get windows shipped with nailing straps attached or loose, which are just flexible metal
with holes in them. Usually they go every 16"-24" inches on the window jamb attached with
a 3/4" screw so as not to penetrate the backside of the jamb and nailed into the framing.
The window can be panned, flashed, shimmed, then metal straps attached and foamed.
The straps are usually about 8" long.
fantastic, thanks guys.db
We just installed some fir windows from a small shop that came without nailing flanges. They did, however, come with small, rigid L brackets similar to Simpson A35 clips. They came screwed to the outside of the 5/4 jamb about 2' O.C. and we screwed them to the face of the sheathing. After the exterior trim went on we foamed them from inside and they won't budge at all.
Also recently installed some Marvin units that came with the world's flimsiest flanges. They really suck, they don't keep the units in plane at all. We got them into plane by attaching 1x4 utility across the outsides of the units (there were several in a row on one wall) and then foamed them from the inside. Again, rock solid. Foam is great for air infiltration and it keeps windows where you want them. I've taken out units from 20 years ago that had foam around them and it holds up quite well.
i ended up going with a system very similar to what davidmeiland describes and ended up using simpson 90 degree brackets on the inside of the wall. The tricky part was that the windows were supplied with sill extensions that extend past the opening so i had to install the windows from the outside and had just enough room to push them in so i could screw on the brackets and fasten.the windows are solid as i have brackets at the corners and every 16". i will use rod and caulk on the inside and foam the gap from the outside.db
The 15 ga nails aren't strong enough, IMO.
Think in terms of 16d finish nails through the exterior casing, into the framing.
And if you want some extra "feel-good" fasteners, use a screw through the jamb, hidden by the sash -- one on each side, and maybe one through the head jamb.
And if you hide the screwheads with the sash, you don't need to worry so much about plugs.
I won't be laughing at the lies when I'm gone,
And I can't question how or when or why when I'm gone;
I can't live proud enough to die when I'm gone,
So I guess I'll have to do it while I'm here. (Phil Ochs)