What to do about stairs and doors during basement energy retrofit?
Good evening,
I’ll be air sealing my basement this winter. House is built in 2004, so I’m hoping there’s a vapor break in the slab. So far tests show no excess moisture coming up from below. However, the basement is rather humid probably due more to the walls and horrible diaper insulation. XPS with two layers of 1/2 in. ply will go on the slab. My concern is, how to deal with the stairs and french doors leading outside? With the floor being raised at least two inches won’t that mean raising the headers in the door? Likewise with the stairs, won’t that create a tripping hazard on the first step? How have others dealt with this? Thanks so much.
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Replies
Adam,
The answers to your questions involve basic carpentry.
When you raise the floor, you need to raise the exterior door. In most cases (assuming we're talking about a pre-hung exterior door), you would use a Sawzall to cut the fasteners that hold the door jambs to the rough opening (or remove the screws if there are visible screw heads). Then you reframe the rough opening and reinstall the door above the new floor.
The best way to solve the stair problem is to remove the existing stairs and cut new stringers, adjusting the riser height to the new reality. The second-best way to solve the stair problem is to remove most of the stair treads and shim under the treads, making the difference in height from riser to riser no more than 1/8 inch.
Amongst the many energy upgrading resources available here, the change in floor height is one aspect of slab insulation improvements that has not been talked about. The options listed above are anything BUT "basic." First, reframing a rough opening side to side is easy. Moving the header is a much different thing. What if there's not enough room to move it up? Second, rebuilding stairs is not basic carpentry, if one wants to do it right. It's fun, but quite complex. And shimming the bottom step only moves the problem to the top step - unless you mean adding the two inch rise in the floor incrementally to each step. Even still, that really doesn't sound like a good idea.
Thanks anyway.
Adam,
Carpenters routinely build stair stringers and re-frame rough openings. It's perfectly understandable that you may not want to do the work, but I stand by my statement that this is basic carpentry.
When I wrote that the "second-best way to solve the stair problem is to remove most of the stair treads and shim under the treads," I meant what I said -- you have to remove "most of the stair treads," not merely a single stair tread. And yes, you have to redistribute the 2 inch difference in riser height among all of the risers, so that the difference in riser height from tread to tread is no more than 1/8 inch.
Again, how do you move a header if there's no room? Most framers don't leave space above the header to the top plate. Can't make the header smaller, that's against code and unsafe. This to me is the single point of failure in the entire project. And I'm sorry, but shimming 14 stair treads sounds like a recipe for nasty squeaks.
Your assumption that I'm not a carpenter or in the trades is odd? Are most forum posters amateurs? I posted with the idea that I would get unique ideas other than apply "basic carpentry."
I'm a licensed builder in Virginia.
No reply necessary.
Thank you kindly.
Adam,
There are different approaches to the header issue. If there are cripples above the header (between the header and the top plate), the cripples can be removed.
If it's a 2x6 wall with a header made of two 2-bys, for example, you can substitute a header made of three 2-bys that aren't as high.
If the header is on a gable wall, it's possible that it is unnecessary, because gable walls aren't bearing any roof load.
Finally, well-attached sheathing provides redundancy for most headers; you can cheat without serious repercussions.
I never assumed that you weren't a carpenter, by the way.
Martin. Will Adam gain enough in comfort and/or energy savings to justify having to tackle the stairs and patio door?
Steve,
That's the question I keep asking myself about my house. My foundation is concrete all around, up to the rim joist. Raising my outside door means a shorter door, or cutting concrete. I'm thinking when I do insulate my slab I'll just use much less near the door, and have a small step somewhere. I could use something like dricore near the door, two panels into the room, the width of the room, and then step up another two inches or so.
Steve,
As I advised Adam in Comment #3, "It's perfectly understandable that you may not want to do this work."
This is a judgment call. Many homeowners would decide that the advantages of an insulated floor aren't worth the hassle of rebuilding the stairs and altering the door.
Adam,
As well as Martins' suggestions I'd add:
- Replacing the dimensional lumber in the header with an LVL.
- Doubling the rim joist above to act as a flush header.
As for the stairs, none of the options sound very palatable. If it are me I'd probably tear out the existing and re-frame with new stringers etc.
Renos frequently make me want to wring the neck of the original builder. Fortunately I live in a small community, so I sometimes get the chance!
I don't know if this would work, functionally or as far as code requirements, but would it make sense to consider put a landing at the bottom of the stairs, at the level of the bottom step, followed by a shallow step down from that to the new floor? I think the minimum allowed step height is 4" and I think you would or could be above that. The question would be whether it would be OK to have that step different from the others. And the other question would be whether that's really significantly easier than rebuilding the stairs.