Insulation under the floor

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.
For Mistress and myself, when you pull up the wood floor, there is no sub-flooring. Just large, hand carved beams, rock, and dirt.

BB,

We finally got every thing worked out between my insurance co, mortgage co, contractor and engineer to start the repairs to our home from Sandy. The engineer was ok, was pretty thorough but my contractor is awesome, does a lot of restorations on these old homes around here and REALLY knows his stuff, even my insurance adjuster was impressed. If you need a GC, let me know, he lives right over the bridge in Stockton, NJ, close by.

As far as insulating the floor, I asked the engineer what he recommends in these old houses. Of course, pulling it up was one of his options as well as the crawl space cement, which isn't an option here, no crawl space. He has seen success with spray foam but it can be hit and miss, usually with limited access points since the crap under the floor tends to be random at best. He has also seen a great deal of what he called "over flooring" with a layer of tyvek, then a new subfloor (variety of materials available depending on application) and the new floor on top. May not be "code" in some areas and would raise your floor slightly but it would kill the draft. This works well supposedly but just sounds a bit weird to me. I remember my dad putting in new wood floors in the old house I grew up in and was really surprised, and angry, to keep finding layers of floor as he started pulling the old floor up - made me think of that!

He started talking about floating floors too but lost me.

Anyone out there know about flooring? Does this over flooring method seem whacked out? What about floating floors?
 
Crap. No solid answers and it actually eliminated some possible solutions. Thanks for the follow up, though.

Right now I have parts of the flooring with a surface temp of 32 degrees.
 
Hah, me too. I told my hubby to leave the fridge pak of soda out of the fridge, the floor was colder anyway!
 
A floating floor is one held down by gravity only. It is not held down by glue or nails or screws.
 
I am seriously frustrated right now.
 
We seem back at what I suggested earlier. Lay down a vapor/wind barrier, rigid foam insulation, plywood or osb and then top flooring. You could consider using structural insulated panels (SIPS) to cover over the existing tongue and groove sub-flooring, but it would be thicker, meaning more ceiling height lost.

A floating floor like Pergo is not tied to the existing floor. It just "floats" on top of the existing floor, sort of like carpet, but without the nailer strips.
 
We seem back at what I suggested earlier. Lay down a vapor/wind barrier, rigid foam insulation, plywood or osb and then top flooring. You could consider using structural insulated panels (SIPS) to cover over the existing tongue and groove sub-flooring, but it would be thicker, meaning more ceiling height lost.

A floating floor like Pergo is not tied to the existing floor. It just "floats" on top of the existing floor, sort of like carpet, but without the nailer strips.
This is easier said than done. In the kitchen it would require all the cabinetry and appliances to be removed and the flooring pulled up. In the living room, it would require losing more head space to a room that does not have a lot to begin with.

With all the talk of "insulating is cheap" this is proving to be otherwise.
 
Insulating IS cheap in a frame house with a traditional basement. Not so much in a stone house....


All these contractors who suggested ideas like putting down tyvek on the old floor to lay a new one, what do they plan to do to prevent the humid air thus trapped between the soil and the underfloor from rotting all your floor joists? If they don't have an answer for that I wonder if they are the expert they claim to be.
 
  • Like
Reactions: save$
Insulating IS cheap in a frame house with a traditional basement. Not so much in a stone house....


All these contractors who suggested ideas like putting down tyvek on the old floor to lay a new one, what do they plan to do to prevent the humid air thus trapped between the soil and the underfloor from rotting all your floor joists? If they don't have an answer for that I wonder if they are the expert they claim to be.
I believe that COULD be done, but you would most definately want some kind of ventilation there (under the floor). Maybe cutting in vents on both ends of the floor to the outside, or cutting in a vent or two and putting a pipe up through a wall and out through the roof with a hydrophonic inline fan, but either way you are talking some serious work to do that. Sadly, I don't think there is an easy way about this.......I liked the product that FlatbedFord had put in his crawlspace. I am seriously considering looking into that for my crawlspace this summer.....

http://neutocrete.com/
 
This is easier said than done. In the kitchen it would require all the cabinetry and appliances to be removed and the flooring pulled up. In the living room, it would require losing more head space to a room that does not have a lot to begin with.

With all the talk of "insulating is cheap" this is proving to be otherwise.

Sorry, sounds like the unconventional construction makes this house a challenge no matter what. I really wonder if it was originally designed to be a residence.
 
Sorry, sounds like the unconventional construction makes this house a challenge no matter what. I sincerely wonder if it was originally designed to be a residence.
It's been a residence since the early 1800's. Possibly further, but we have not checked the records beyond that as to how the structure was used.

The issue seems to be that whenever the house was added-on to, or renovated, over the last 200+ years the updates have been done by cutting corners.

Spoke with my father in-law. When they first bought their farmhouse they used hay bails around the parameter in the areas that they had draft problems. I'm going to give that a try and see if that gives us any hint as to where the leaks are coming from.
 
The issue seems to be that whenever the house was added-on to, or renovated, over the last 200+ years the updates have been done by cutting corners.


I hear that! I generally have more trouble undoing bad post-1960 renovation work than with anything to do with the original structure....
 
It's been a residence since the early 1800's. Possibly further, but we have not checked the records beyond that as to how the structure was used.

The issue seems to be that whenever the house was added-on to, or renovated, over the last 200+ years the updates have been done by cutting corners.

Spoke with my father in-law. When they first bought their farmhouse they used hay bails around the parameter in the areas that they had draft problems. I'm going to give that a try and see if that gives us any hint as to where the leaks are coming from.


I used to do that in CT. It helped a lot, but it also attracted lots of rodents that took advantage of the warm safe nests.
 
Wow! tough problem! lemme take a stab at it, nothing to lose.

I would first inspect your sills (if any). If they rest right on the ground they may be your first priority. If they are sound, consider jacking up the house to give your self some working room. If they are not, jack up the house and replace them. You can then pour or lay up a stem wall (on a footer), or do one with treated lumber.

If you are lucky, you may have a section with lower grade along one side of the house, in which case you could dig down to achieve your crawl space.

This may sound expensive, but get some estimates.

Google "crawl space heating plenum" for an alternative treatment once you have a workable space.

Ehouse
 
Wow! tough problem! lemme take a stab at it, nothing to lose.

I would first inspect your sills (if any). If they rest right on the ground they may be your first priority.
Sills?

If they are sound, consider jacking up the house to give your self some working room. If they are not, jack up the house and replace them. You can then pour or lay up a stem wall (on a footer), or do one with treated lumber.
You can't jack up a stone house.

If you are lucky, you may have a section with lower grade along one side of the house, in which case you could dig down to achieve your crawl space.
Not an option.

This may sound expensive, but get some estimates.
Every option appears to be a) expensive and b) not a complete solution.
Thank you for taking a stab at it, though. There must be a solution out there.
 
  • Like
Reactions: Hearth Mistress
I used to do that in CT. It helped a lot, but it also attracted lots of rodents that took advantage of the warm safe nests.
Well, Mice already like to visit. Maybe if we give them a home outside they won't come in? ;hm
 
I didn't see where you said it was stone, sorry, but then the walls must continue down to some kind of footer right? So what precludes you from excavating a crawl space? I'm not trying to be dense, but by excavating I mean hand digging or having it dug. You must have some access to be able to tell us what's down there.
 
Looks like BAR and I are SOL. My GC is awesome, it was the engineer that made the floor recommendations. But ehouse to answer your question, no, there is no sill plate or footer to speak of. To be honest, after really looking at how this house was built, I can't believe it's still standing and hasn't crumbled down the hill side!

It is a bank barn, literally built into a vertical acre of slate. It was built as a barn to have a place for mules and their keepers to stop along the way when they use to shuttle coal on the Delaware Canal (across the street) from Bristol to Easton, PA. The original part of the house, built in 1860 is stone, no foundation, just literally sitting on the slate and dirt. The kitchen that was added at the turn of the century also, no foundation, sitting on rocks and dirt.

As far as trapping moisture between the layers of the floor and rotting the floor joists, they have been on rock and dirt over 100 years, don't know what's left down there to rot :)

We tried the hay along the exterior kitchen wall last winter. Damn mice brought the hay IN the house and made nests in the cabinets!

The Sandy repairs/ rennovations will be starting this week, if the township has my permits ready tomorrow. I'm hoping that a new roof and siding will cut most of the draft, then, we will tackle the kitchen floor ;)
 
Thinking outside the box here. Pull out the fridge smash the ice maker valve with a hammer go out to dinner. Report damage to insurance co. Voila!! ;) .Seriously, Having worked on many older homes similar to yours, most solutions are going to be costly. The most cost effective would be to BGs idea of laying down tarpaper , foamboard, subfloor, and then finish flooring. This works well but will add a couple of inches to your flooring height. Tearing up the subfloor to expose the framing making it possible to insulate properly is quite an undertaking as well. Do you have any idea how much space is between the framing and the dirt?
 
  • Like
Reactions: Hearth Mistress
Nuts. there's got to be a solution. What about a loose blown in fill such as Perlite? Won't hold in moisture but will slow air flow and insulate, and a flooring jack to tighten up the plank floor (expansion joint at each wall). Combined with the renovations tightening up the upper structure so air's not being sucked out above and pulled in below.
 
0"

That is an exact measurement.

Nuts!! Not much room there.When remodeling a room it is not an unrealistic amount of work to tear up the existing to the framing..Destroying a perfectly good floor to access the underside seems a little overly excessive and costly though.
 
If you have 0" between the sill and the dirt then how do you have any crawlspace? Slab jack. Apparently the subgrade is quite firm and you do not need footers. Can you just pump grout into the area between the floor and the dirt to seal up the leakage? The beams will be unnecessary if the entire floor becomes a slab on grade setup.

You do not need to remove cabinets to appy a new floor with proper air seal. Of course it would be better but the cabinets themselves should be sealed fairly well.

Lastly, You have concluded that no work can be done to prevent air from passing through the floor. That air got under your house from the perimeter somehow. Seal that leak at the perimeter. Unvent your crawlspace. brick and mortar around the perimeter to a height above the sill.

I am most confused about how you state that the sill plate is on the dirt but somehow air is coming up through the floor.
 
Highbeam, not sure how it got confused but there is no crawl space at my house or BARs. We live about 10 miles from each other and there are a lot of really old houses around here. Someone else posted an awesome solution for spraying concrete in the crawl space but no good to us.

I'm not sure what anything else you said means. All I know is I don't have a foundation, it's dirt and slate with the 1st floor being 18" thick fieldstone walls. There isn't a plumb line anywhere in the house, floor, ceiling, etc. I still have plaster and horsehair in my attic and when the engineer was up there assessing damage from hurricane Sandy he was pulling hand forged cut nails out of the beams as souvenirs. Old, old construction makes for messy repairs or renovations.

You are right that the air coming up from the floor is being pulled in from the perimeter but even plugging up every little crack we can find between the bottom of the siding and the ground with expanding foam, it's still not enough. It only seems to be an issue in my kitchen, the part built turn of the century is my draft hole. If you stand with a lit match in front of any of the drawers or cabinets, the draft will blow out the match. The stove is in the adjoining room and doesn't help matters sucking the cold air in even more.

It's a challenge for sure but I'm hoping that with new insulation and siding it will help some. My GC dropped off samples of Handi Plank today, evidently this cement board siding is a great insulator, we will know soon :)
 
  • Like
Reactions: BrowningBAR
Status
Not open for further replies.