I’ve installed groups of windows (see attached), and want to seal the nail flanges with some butyl flashing tape. But my problem is that the gaps between the windows are only about 1.75″ wide and most of the flashing tape I can find is of the 4″ variety. I know I could cut it down but I’ve got about 65 windows to flash and cutting it down seems incredibly time consuming. Any ideas?
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M-
nothing is attached to your post.
I don't know if this would work, but you could try to cut down a roll of flashing tape on a bandsaw. If you bought Grace Ice and Water Shield (basically the same material is Vycor) in the 36" rolls you could cut custom width rolls to whatever size you need.
You might want to experiment with a 4" roll first. The heat/friction might make a big mess out of the thing.
>>> The heat/friction might make a big mess out of the thing.
Yes. Mess of the blade and bandsaw too. DAMHIKT.
sorry... here's the attached drawing
Try metal roofing supplier. They have butyl tape as narrow as 1/2"
I would prefer Vycor flashing cut down instead of tape though.
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Why would you prefer the Vycor over Butyl? Will it hold better?
Easier to work with.Hold better?I use nails to hold the window in, not the tape. Am I missing something?
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I meant is the Vycor going to stick better to the vinyl flange than Butyl wood over the years. Hold the windows in......what kind of an idiot do you think I am? Don't answer that. I'd rather use Vycor myself but cutting 4" strips down to 2" strips for about 1000 feet seems like a royal pain in the ####. But I guess you gotta do what you gotta do.
I could have it done in twenty minutes or so!Lay out a scrap of ply on sawhorses at least as s long as tallest Vycor needed. Mark lengths on the play. Roll out Vycor and cut to length. By figuring ahead, I'd know how many.Then use a straightedge and a utility knife to rip them just so.
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>>> I use nails to hold the window in
I thought you used Piffin screws. If you don't support your company's products who will?
Sorry - you misunderstand the background of piffinscrews.The phrase came up because I hate using sheetrock screws for anything other than hanging sheetrock
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Thanks Piffin, but I was aware of that. That was simply my poor attempt at humour (only kidding), left the <G> out thinking it was obvious {{insert ;>) here }}
(I too hate drywall screws, never use the cheap galvies, switched to deckmates)
Be careful using Vycor. It is petroleum based and window companies with vinyl nail flanges are now specifying Butyl based products because the petroleum reacts and breaks down the vinyl. Granted it will take forever for this to happen, but it could still void the warranty. Read it.
Mike,
I have wondered about this. My first window job was Andersen 400's that I installed using Vycor. I know that PVC and asphalt don't mix. (Basically vinyl nailing flanges and petroleum Vycor).
I don't recall exactly who I called (maybe Grace) but nobody seemed to think it was a problem then.
What mfg of butyl do you use? I haven't really researched it lately, but have you had any experience with Tyvek's flashing tape?
I use the Tyvek StraightFlash. I seems to work well. No problems yet. I use the Marvin sill guard on all of the sills instead of the flexible tape.
Not familiar w/ the Marvin sill guard. I will check into that one. Do you use it because you install Marvin windows or cause you just like the product?
FWIW, one problem I have with Vycor, is that it doesn't stay adhered to Tyvek very well and if you read their instructions, mechanical fastening is required/recommended? to ensure a proper seal.
"FWIW, one problem I have with Vycor, is that it doesn't stay adhered to Tyvek very well and if you read their instructions, mechanical fastening is required/recommended? to ensure a proper seal.".........I always put the flashing to raw wood,my thinking is that any water that penetrates the tyvek, tar paper or whatever will get behind the flange and leak. defeating the whole purpose of the product,What am i missing, doing it the other way?DAVE
Do you then tape the Tyvek to your Vycor, or just leave it overlapped?
Perhaps that is a better way. I have always lapped the Tyvek over the head flashing.
Sides - Vycor to Tyvek
Bottom- Vycor to bare wood sill, over the Tyvek, then install window on the Vycor.
Of course this assumes you have wood sheathing. My house, I got wood fiber board. Nothing sticks to that.
One other house I resided, had 1" polyiso insulation- poor adhesion there too.
Hey V.,
I normally use Grace I/W cut down to strips. The Grace seems to stick better and is cheaper(sorry, cost effective). No I don't tape,and no to sticking to Tyvek on sides/bottom. Always just use I/W as primary flashing. Cover nail flange to wood, never on tyvek. We usually install wood lap siding with a built up 5/4x4 wood trim, 5/4x6 head and sometimes I will use 30lb felt strips 8-10inwide around the window on top of the tyvek. More to level out the area than anything else. But it does provide another level of protection. DaveThe way your windows are configured I'm not sure I would worry about using 1 1/2in. tape(I/W), because the nail flange is doubled up. If I was using 5/4 trim I would infill with 3/4 material applying a good sealer caulk like GEOCELL or similar prior to installing wood and only using minimum nailing(if any).
Both, I like it for the "belt and suspenders" approach. It seems that when I have replaced windows 20 yrs old plus. It is the sills that need the most attention. The sill guard sits on the framing sill and has a flap up in the interior preventing any water from leaking on the sill. Any water that gets beyond the flashing is directed out beyond the Tyvek. I'm not sure if all of this work is completely necessary, but I definitely think it is worth using it on doors. And then again, sometimes I think that there are way too many steps that the window manufacturers are putting in place. I think it is from the installers that do not know that water runs downhill, not properly flashing and the manufacturers are idiot proofing installs. OK off my soapbox......
Butyl is a petroleum product also. There is a difference in asphalt base products and butly, but they are both hydrocarbon materials. Butyl is cooked up from natural and synthetic oils, asphalts are from "bottoms" in the distillation process.
Dave
We cut Grace I&W all the time with a Sawzall and also on the tablesaw sometimes. You shouldn't have any problem cutting flashing material on a roll as long as you do it cold, the tablesaw will leave a straighter edge when cutting narrow strips.
I would like to know why you have to seal between the windows to start with????? If the units were set as a "group" they should have a factory applied cap and not need to be flashed at the mulls!!! Sound to me like someone is passing the liability on. Or just poor design! I have never seen any instruction pamphlet or video on flashing multiples at the mull. They all concentrate on the perimeter of the opening. Just curious
The units weren't set as a group. They were individual windows that I installed with the nail flanges overlaping each other, except (obviously) around the perimeter.Basically I've got 2x6 walls and an intentionally oversized window opening which I then framed out with 2x4's sitting flush with the inside. Then I used 2x4's for the vertical and horizontal mulls which leaves me with 6 individual window openings that are inset 2" from the outside wall plane. Then, I installed the bottom middle window first, then the 2 bottom side windows whose flanges overlap the middle window flange. Then reapeat the process with the top (transom) windows. Resulting in about a 1.75" gap between and around every window. My plan was to either buy some Butyl tape (1.5") or cut down some Vycor and cover all of the nail flanges, but maybe I don't need to tape them at all. I caulked the heck out of each window, but hey you guys are the experts. What do you think?