Sill Seal - Y or N

[Mwaters]

I am having a 20x30 detached garage built right now. I have asked the framers to put down a sill seal between the treated bottom plate and the 1 foot stem wall. I kind of got the "Why?" look from them, but they went ahead and did it any way.

Well, time comes to frame in the window after its wall has been stood up and bolted down to the foundation. One of the 2x6 studs under the window sill framing was just a little taller that the other two in that space even though they were cut the same length. The framer looks at me (since I was watching/curious) and says to take a look.. "Do you know why that board is too tall?", he says. And it was indeed 'proud' as one might say..he continued "..because the places where the bolts/washers were tightened down had compressed the foam, it's caused the middle area between the bolts to stand higher due to it not being compressed". It was hard to argue his point really when you see a kind of waviness to that plate the studs are sitting on. I guess the only real way to solve it would be to out in twice the anchors - every two feet, versus four.

He's being pretty particular about getting things just right and he says that it could throw off his top plate just a bit because it will be higher in all the sections between the bolted bottom plate. He ended up cutting that one stud down a tiny bit so that the windows sill would sit dead flat but his contention is things like the foam sill seal are often more gimmicky than useful. I said I was just concerned that there be a capillary break between the foundation and the bottom plate for any water that may wick up from the concrete. Again, I kinda got the 'Huh?" look from him.

Is he right? Should I not really be concerned about water making its way to the bottom plate? While I will insulate and cover the walls, I don't really need it to be an air tight structure.

Thoughts?

Mike

 

[Chris705]

Stand firm with your intuition.....

 

[ItsNemo]

Sill gasket is definitely a good idea...I don't understand how it messed with a window frame though? Can you take a picture of the problem?

 

[Dumber than lumber]

To the OP - when I read Sill Seal i was thinking of something that comes out of a tube (like caulk) or something like 3M VHB that has adhesive on both sides. Old timers giving you the "Huh?" look might mean "you dumb fluck". But on being screwed/bolted down too tight I would try to slack off the fastener a tiny bit. Or use a plane or multimaster to smooth out the bump.

 

[htmdude57]

Of course I would want the draft sealing gotten by using the foam. But if he knew that would happen, why didn't he suggest a couple beads of caulk under the bottom plate?
(we must have been typing at the same time)

 

[Mwaters]

Here's a photo of the 2x6 in question. He cut it down slightly so that window sill is flat. You can see that it sits right about in the middle of the two foundation bolts.

 

[Mwaters]

I did suggest maybe loosening the fasteners and found they thought that was silly.

To the OP - when I read Sill Seal i was thinking of something that comes out of a tube (like caulk) or something like 3M VHB that has adhesive on both sides. Old timers giving you the "Huh?" look might mean "you dumb fluck". But on being screwed/bolted down too tight I would try to slack off the fastener a tiny bit. Or use a plane or multimaster to smooth out the bump.

 

[ItsNemo]

Okay, that's what I expected, just normal framing...How tight did he bolt the damn thing down? Every house up here is framed with sill gasket and it's NEVER an issue.

 

[Mwaters]

Okay, that's what I expected, just normal framing...How tight did he bolt the damn thing down? Every house up here is framed with sill gasket and it's NEVER an issue.

Not sure. They used a 1/2" electric drill. Much like I would use to remove lug nuts. A Dewalt, I think.

 

[ixlr8]

When I did my build, I used seal seal and the builders put the sheathing on before they raised the wall. This would have prevented the issue you are having with the bolts compressing the SS to the point the wall height was no longer uniform.

 

[PCustoms]

Any reason they didn't use a double sill plate?

 

[pcmeiners]

Any reason they didn't use a double sill plate?

The builder likes wavy sill plates
That plate would never fly in NYC, never.

What is the thickness of the plate?

 

[Mwaters]

The builder likes wavy sill plates
That plate would never fly in NYC, never.

What is the thickness of the plate?

2x6 pressure treated

 

[50pascals]

Any reason they didn't use a double sill plate?

So he could ***** about his mudsill not being perfectly straight, and throwing the roof off.

But to the OP - On concrete, a couple beads of caulk would've worked too. And the sill seal is not for water, it's for air and insects.

 

[Viper98912]

My last house was built with sill seal. Current house not. Now I'm going back throughout the entire perimeter of the house trying to squeeze in expanding foam as I've got MANY more critters inside this house than the last. I assume it's due to the daylight/gaps I can see.

I recommend yes to the sill seal.

 

[Moss]

I think the issue you are showing is a reason you would want a sill gasket. The gap between the bolts now has the gasket to stop air infiltration. Unless I am misunderstanding it's almost laughable he's blaming that on the gasket.

 

[23ford]

When i saw the title thought were talking about a tin shield with caulking on the bottom side

 

[spudley]

I believe either the the concrete has a slight dip or the framer cut that trimmer shy. Either way, that sill seal will squish tight once the wall sheathing and trusses/rafters and roofing are on.

As others stated, sill sealer forgives that slight variation in forming.

 

[capterik]

i have no idea what they used as a sill seal, but the one i use, takes zero effort to collapse, issue is not seal but something else

 

[CraigStu]

You are talking about this stuff right?
https://www.ebay.com/i/383703488773...1291&msclkid=7deaf745940017d3e83aa83a80dd9837
I thought that the bottom plate being of treated lumber and sill seal being installed were both code requirements. Seems to me he is full of it and just using this to dig at you for requesting extra work. BTW I have never seen a window fit so tightly that it wouldn't go into the rough opening due to a 1/8" variation. I though all rough openings were 1/4-3/8" oversized so the window could be shimmed for a perfect fit.

 

[calstar]

Don't see how that would effect the top plate, window opening right?, opening is always a bit larger than the window to allow for shims/fitting, and there is no connection to the cripple in question to the top plate, just doesn't make sense it will "raise" the top plate. Framing isn't fine carpentry, if thats the worst you've seen on your project I think you're OK.

 

[MikeF2316]

I've never seen any framing that's been done to tighter dimensions than the thickness of sill gasket. I'd always use it.

 

[Mwaters]

You are talking about this stuff right?
https://www.ebay.com/i/383703488773...1291&msclkid=7deaf745940017d3e83aa83a80dd9837
I thought that the bottom plate being of treated lumber and sill seal being installed were both code requirements. Seems to me he is full of it and just using this to dig at you for requesting extra work. BTW I have never seen a window fit so tightly that it wouldn't go into the rough opening due to a 1/8" variation. I though all rough openings were 1/4-3/8" oversized so the window could be shimmed for a perfect fit.

Yes, that's the stuff.

 

[ItsNemo]

I've never seen any framing that's been done to tighter dimensions than the thickness of sill gasket. I'd always use it.

That's such a good point...the 1/16" that the sill gasket adds is way tighter than most framing gets banged together.

 

[nmk_61802]

Once the roof is loaded, it shouldn't matter, the entire wall will press down on the bottom plate further compressing the gasket. I would guess at that point the bolts will also need re-tightened.

 

[nadogail]

My home was built in’88 and the bottom plates (sills) were bolted to the slab, but not sealed. We noticed the wall to wall carpeting developed a brown stain around the edges. Investigation revealed that the lack of sealing allowed air infiltration and the stain was trapped dust. The carpet was pulled back from the walls and caulk applied to the bottom plates.

Apparently there was no requirement at that time to seal those bottom plates. The builder incorporated sealing the bottom plates in his standard practice from then on.

 

[ddurrett896]

Any reason they didn't use a double sill plate?

What's the purpose of a double sill?

 

[Bolson32]

I think the issue you are showing is a reason you would want a sill gasket. The gap between the bolts now has the gasket to stop air infiltration. Unless I am misunderstanding it's almost laughable he's blaming that on the gasket.

Exactly my thought. He's being ridiculous.

Sent from my SM-N981U using The Garage Journal mobile app

 

[NUTTSGT]

My opinion, not that it means much... Use sill seal, your contractor is full of **** and old school.

 

[dcg9381]

On this, I used http://www.conservationtechnology.com/building_gaskets.html - they have both a 2x4 and a 2x6 gasket that replaces the traditional foam "sill seal" that goes into framed homes around here. You would or wouldn't be surprised how many times I had to have the framing crew correct the install of these things - anything "new" throws people for a loop. I got the idea from Matt Risinger (who I'm quite sure I can't afford). One some of his homes he goes so far as to then seal the 2x4 or 2x6 to the concrete plate with something in a tube...

 

[dfiler2]

We always use sill seal and I'm not buying that a window wouldn't fit because of it, but I might use that excuse next time it happens. It looks like he is doing a very nice job.

 

[TractorJeff]

I would hazard a guess that the stud was cut wrong or the concrete underneath caused the waviness? Putting an addition on a poor (flat) foundation for a guy right now. They put down Foam Seal (similar), then wooden shims to get the sills all level. He wanted the Gaps spray foamed for Bug and Air infiltration. Customer wants? He gets!
BTW: I checked it the next day after the floor was laid and it is still flat and level!

 

[dcg9381]

Builder here shimmed all the window sills slightly outward before installing the windows. I agree, the tolerances on installed windows are way over what any sill gasket would cause problems with. IF you install the windows that tight - under 1/16th, you can't get foam into the framing to seal the window anyway.

Windows I bought had a dimension spec for the opening - it was basically over 1/2" all the way around on most of them.

 

[madhatter]

I don't believe for a second thats due to the seal, more likely uneven concrete or 'maybe' they lapped the sill seal there, but I can't believe that would even cause that. What is that stuff 1/8" thick uncompressed?

 

[Mwaters]

He wasn't implying that the windows would be tight. Only that the foam was responsible for the high spots on the bottom plate as opposed to the places where it was bolted down. I'm thinking if that was know to be a thing, couldn't he have cut a small square of the seal and doubled up at each bolt to account for any 'crush' the foam might experience?

Anyway, the sheathing is now up and will roll trusses and stuff starting Monday. The foam saga not withstanding, I am very pleased with their work. They take their time with things and are not in a rush and the three of them work well together and are conscientious about leaving the site clean at the end of the day. The company brought in a port-a-potty, too, so they wouldn't have to bother us for the bathroom. Maybe that's standard practice, though. This is my first project like this.

We've lived here since 1993 and only had a carport to do any maintenance or projects in so we are excited for a garage finally. Also, a failed garage build exactly one year ago had us down in the dumps as we had to deal with getting our money back and the entire structure, and foundation, removed entirely just so we could start all over again with new plans, permits and contractors. Once this building is done, we are definitely throwing a party!

 

[Firebrick43]

I am having a 20x30 detached garage built right now. I have asked the framers to put down a sill seal between the treated bottom plate and the 1 foot stem wall. I kind of got the "Why?" look from them, but they went ahead and did it any way.

Well, time comes to frame in the window after its wall has been stood up and bolted down to the foundation. One of the 2x6 studs under the window sill framing was just a little taller that the other two in that space even though they were cut the same length. The framer looks at me (since I was watching/curious) and says to take a look.. "Do you know why that board is too tall?", he says. And it was indeed 'proud' as one might say..he continued "..because the places where the bolts/washers were tightened down had compressed the foam, it's caused the middle area between the bolts to stand higher due to it not being compressed". It was hard to argue his point really when you see a kind of waviness to that plate the studs are sitting on. I guess the only real way to solve it would be to out in twice the anchors - every two feet, versus four.

He's being pretty particular about getting things just right and he says that it could throw off his top plate just a bit because it will be higher in all the sections between the bolted bottom plate. He ended up cutting that one stud down a tiny bit so that the windows sill would sit dead flat but his contention is things like the foam sill seal are often more gimmicky than useful. I said I was just concerned that there be a capillary break between the foundation and the bottom plate for any water that may wick up from the concrete. Again, I kinda got the 'Huh?" look from him.

Is he right? Should I not really be concerned about water making its way to the bottom plate? While I will insulate and cover the walls, I don't really need it to be an air tight structure.

Thoughts?

Mike

It has been said by several wisemen, “the sign of a true craftsman is how they deal with mistakes”. Your framer is dealing with it poorly.

Multiple ways people have already alliterated as to why it happened and he did his job to correct for it but he is an idiot to blame the sealsill, something that should be in every build. And it’s not per say for moisture, that is what flashing and drainage plains are for, its to seal air and bugs out. Caulk does not perform as well as it will debond with differential expansion of the wood/concrete.

My thoughts are that your framer is a man of limited thoughts. He has been shown how to pound nails and cut boards but has not idea as to the building envelope as a whole.

 

[gearhead1]

When I built my shop, I had a stem wall with cinder block. Since they’re 8” wide, I used a 2x8 ground contact rated bottom plate. I could only find 6” foam readily available. So I took a roll of tar paper and cut it on the table saw to 8” (maybe it was 8-1/4 or something, you get the idea) and put that down, then put the 6” on top. With just the weight of the 2x6x12 studs and double top plate, it squeezes the foam pretty good and you can’t tell it’s not 8” wide foam.

I did not want the ground contact rated bottom plate touching the block at all, but I wanted it sealed. I’m sure I could have ordered 8” foam somewhere, but I didn’t want to wait a week when I was ready to build. I’m sure some will say it’s not needed. My response is I’m an engineer and when I do things, I want it right and I want it lasting forever. I will overdue something like that before I under do. There are other things I’m ok with ‘good enough’ but a permanent structure that costs a lot of money isn’t one of them. I want it done right the first time.

 

[Tduby]

What's the purpose of a double sill?

I’m curious too. Only time I ever did a double bottom plate was partition walls in the basement or garage so I could space the wall 1.5 inches off the ground for moisture.

 

[ItsNemo]

When I built my shop, I had a stem wall with cinder block. Since they’re 8” wide, I used a 2x8 ground contact rated bottom plate. I could only find 6” foam readily available. So I took a roll of tar paper and cut it on the table saw to 8” (maybe it was 8-1/4 or something, you get the idea) and put that down, then put the 6” on top. With just the weight of the 2x6x12 studs and double top plate, it squeezes the foam pretty good and you can’t tell it’s not 8” wide foam.

I did not want the ground contact rated bottom plate touching the block at all, but I wanted it sealed. I’m sure I could have ordered 8” foam somewhere, but I didn’t want to wait a week when I was ready to build. I’m sure some will say it’s not needed. My response is I’m an engineer and when I do things, I want it right and I want it lasting forever. I will overdue something like that before I under do. There are other things I’m ok with ‘good enough’ but a permanent structure that costs a lot of money isn’t one of them. I want it done right the first time.

For future reference, you just buy the 3.5" stuff for 2x4 and do two strips.

 

[gearhead1]

For future reference, you just buy the 3.5" stuff for 2x4 and do two strips.

Unfortunately they didn’t have that either. But yeah, that would have worked.