Replacing windows.

b_corwin

I am in the middle of a bathroom remodel and am considering replacing the old windows while the bathroom is gutted. The house has wood siding on top of a layer of sheathing that is coated in tar paper. The wood siding goes directly up to the edge of the window. IE there is no trim around the window.

I am thinking the best way to go about doing this is to cut the existing siding to say 2 inches away from the existing window, tear the old one out, put in a new on with a nailing flange, and add proper trim around the window. My question is how do I go about waterproofing around the window? Most resources I see show putting up a layer of 6" ice and water barrier around the nailing flange. Will this even stick to tar paper? Also, as I am only intending to cut the siding back 2 or so inches, if I were to ice and water shield just that 2 inch area, is that sufficient?

Finally, it seems I need to apply some flashing at the top of the new trim as well?

Just wondering if this plan makes any sense.

Thanks much
Brian

Tom Struble

what you propose will work,but you need to pay close attention to your water proofing details

i would cut back a little farther,3'' min

the hard part is not compromising the tar paper underneath as that is where you will be draining on to

yes a metal drip cap will be needed,make sure it gets under the paper and keep the bottom edge of the siding at least 1/4'' off the drip

it wouldn't hurt to prime the cut ends of the siding and caulk where the siding meets the sheathing before you apply the trim

Gary in WA

pp.3-6, and page 8; http://www.mtcc1170.com/images/BCRainScreen.pdf

Gary

__________________

b_corwin

Thanks a lot guys, I will be sure to waterproof it as best I can. I was going to cut the siding out with my multimax and i guess I will just slide a piece of sheet metal behind the siding to protect the tar paper.

B

b_corwin

Actually I'm confused, It appears from what I can see that in the link from gbar in wa the top flashing goes on top of the ice wand water barrier but under the paper. Is this correct?

So when I cut the siding back to fit my trim, I should lift the existing paper and put the ice and water shield under the tar paper, and put the flashing edge in between the ice and water and the existing tar paper? I had thought I could put the ice and water over the existing tar paper.


b

Dwoodsmith

The flashing does go behind the paper. This prevents any water that might get behind the siding to not then be able to get behind the flashing.

b_corwin

So In this case, I put the window up, ice and water over the nailing flange, cut the siding for the trim and then as I mount the flashing over the trim, cut the tar paper/icewater barrier and slide the flashing in.

b

Dwoodsmith

You got it! as the other guy said, leave a little gap over the drip edge so the material doesn't soak up water. When I'm nailing trim around windows and the ends of the siding around that, I like to put a little silicone behind the nail heads before I drive them home.

b_corwin

Thanks much, Looking forward to replacing these windows.

B

Dwoodsmith

Print that statement out so you can read it after you're done.

Tom Struble

[quote=b_corwin;578921

I had thought I could put the ice and water over the existing tar paper.

b[/quote]


only over the tar paper at the botton,either way at the sides but at the top it always goes under