ATLANTIC CENTRAL All very valid and interesting if I am building a new structure, especially in a colder climate. Of interest to, but not of much practical value for those dealing with existing structures with no external insulation.
All very valid and interesting if I am building a new structure, especially in a colder climate.
Of interest to, but not of much practical value for those dealing with existing structures with no external insulation.
Right, and that was my point in linking it: at one point he says that its extremely difficult to seal and insulate a basement in a NEW home under *ideal* conditions, and basically impossible to do with retrofits of existing homes.
Andy
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Milwaukee native modeling the Milwaukee Road in 1950's Milwaukee.
https://www.flickr.com/photos/196857529@N03/
The Milwaukee Road Warrior Here is a great video going into the nuances of basement wall insulating for exterior walls. https://www.youtube.com/watch?v=kwn0Vjw_ji0
Here is a great video going into the nuances of basement wall insulating for exterior walls.
https://www.youtube.com/watch?v=kwn0Vjw_ji0
Here in the Mid Atlantic, winter is cold, but not like the upper mid west, and a great argument can be made for little or no basement insulation here.
We insulate existing sills with fiberglass here all the time with no moisture issues, BUT, we are careful to only insulate to the width of the sill plate, still allowing the top of the foundation wall to breath, just as was discussed in the video.
If you want to build the best insulated frame house and basement foundation house, we use Weaver Precast foundations and ZIP system insulated sheathing.
https://zipsystemrevolution.com/?gclid=Cj0KCQiA04XxBRD5ARIsAGFygj-5m3Djj9OCwoQi0iylAnp2qhd4zQ40APk7j29mHsfV_-JQDEJxFz4aAh1AEALw_wcB
https://weaverprecast.com/
All that info in that video, is why my basement layout room (the whole basement) will not have drywall walls........or interior insulation.
I'm happy to have to heat it from a max heat loss of 55 degrees, and a dehumdifier makes that a cool comfortable space in the summer with no A/C cost at all.
Sheldon
NittanyLion ATLANTIC CENTRAL York1 I'm not sure about the places you all live, but in my area, all basements built in the past 20 years have to be insulated floor to ceiling, regardless of how deep. Yes, that applies to new houses, it has been part of the IRC for about 20 years. But even in a renovation, most jurisdictions do not require bringing that up to current new construction standards. The reason for that code is simple, to reduce energy costs and "save the planet", a conversation not for this forum. I will just say, as a building engineering professional, it is questionable how much energy it actually saves, and at what cost in other problems and added building cost. Sheldon Fairfax County VA requires it for all renovations, which has thrown a bizarre wrench in my basement refinishing plans. The wall was originally furring strips and paneling on the block wall. The only doorway is in the corner of the basement and the door frame is pretty much up against the block. With the thin furring strips and paneling, this isn't an apparent issue. We had to pull the paneling down on that wall as part of the waterproofing we had done. Now, if I refinish that wall to code, the wall actually intrudes into the doorway. Fantastic.
ATLANTIC CENTRAL York1 I'm not sure about the places you all live, but in my area, all basements built in the past 20 years have to be insulated floor to ceiling, regardless of how deep. Yes, that applies to new houses, it has been part of the IRC for about 20 years. But even in a renovation, most jurisdictions do not require bringing that up to current new construction standards. The reason for that code is simple, to reduce energy costs and "save the planet", a conversation not for this forum. I will just say, as a building engineering professional, it is questionable how much energy it actually saves, and at what cost in other problems and added building cost. Sheldon
York1 I'm not sure about the places you all live, but in my area, all basements built in the past 20 years have to be insulated floor to ceiling, regardless of how deep.
I'm not sure about the places you all live, but in my area, all basements built in the past 20 years have to be insulated floor to ceiling, regardless of how deep.
Yes, that applies to new houses, it has been part of the IRC for about 20 years. But even in a renovation, most jurisdictions do not require bringing that up to current new construction standards.
The reason for that code is simple, to reduce energy costs and "save the planet", a conversation not for this forum. I will just say, as a building engineering professional, it is questionable how much energy it actually saves, and at what cost in other problems and added building cost.
Fairfax County VA requires it for all renovations, which has thrown a bizarre wrench in my basement refinishing plans.
The wall was originally furring strips and paneling on the block wall. The only doorway is in the corner of the basement and the door frame is pretty much up against the block. With the thin furring strips and paneling, this isn't an apparent issue. We had to pull the paneling down on that wall as part of the waterproofing we had done. Now, if I refinish that wall to code, the wall actually intrudes into the doorway.
Fantastic.
Here in Maryland, the waterproofing would be considered a "repair" and would not require a permit.
And thereby the replacement of the wall would be considred a repair and not require a permit. And, even if the inspection authorities were involved for some additional reason, they would allow the wall to be "restored" to the way it was, as it would be part of a "repair".
I just moved out of my 1901 Queen Anne house that I restored in 1996. We did extensive work to the front porch. We were not required to meet new codes regarding railing height or balaster spacing - because it was a repair, we repalced damaged materials and put it back exactly the way it had been.
The application of such rules varies from area to area....
ATLANTIC CENTRAL So, that's something I would never do, attach furing to block walls and then put drywall on them, with or without insulation. In my view, the only proper thing is to build a stud wall that stands an inch way from the block/poured concrete wall. A wall that can be properly plumbed, properly wired, and properly insulated. Which I am not going to do in my new layout room basement. The block walls are just fine, no one will see them once the layout backdrop is up. And I am not giving up 1 foot of layout space. As for permits for this kind of work, yes more and more it is coming to that everywhere. But not so much yet where I live. I will be retired before they get that nosey here. Sheldon
So, that's something I would never do, attach furing to block walls and then put drywall on them, with or without insulation.
In my view, the only proper thing is to build a stud wall that stands an inch way from the block/poured concrete wall. A wall that can be properly plumbed, properly wired, and properly insulated.
Which I am not going to do in my new layout room basement. The block walls are just fine, no one will see them once the layout backdrop is up. And I am not giving up 1 foot of layout space.
As for permits for this kind of work, yes more and more it is coming to that everywhere. But not so much yet where I live. I will be retired before they get that nosey here.
This is why I opted to rip it all out and start over. That's how mine was done. ANd even in palces where they used studs and not furring strips, it was just paneling nailed right to it, and there was no attempt at all to set a standard spacing. Some would be 12" apart, then the next one would be spaced out 18", then you might get one at 16"
If I did it all myself, forgetting about how much longer it woudl take me, it wouldn't be as good as what I'm getting, but it would have been a whole lot better than what was there. I know better. I also have some sense of what I don't know, and will research it before just trying to do it if I'm not sure. No, they didn;t have the internet when the old work was done, but there were books - we had a whole series of them that I read cover to cover, several times over, as a kid, that showed all sorts of how tos for building things.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
When I finished the laundry room/storage area of our basement years ago I only installed strapping, insulation and vapour barrier to about 12" below grade. That left about 30" of exposed cinder blocks above the floor. I'm kind of glad that I left part of the wall exposed because very occasionally there has been a bit of moisture that enters between the bottom of the wall and the floor. As a result there has been a tiny bit of mould growth, but things dry out very quickly. If I had extended the wall all the way to the floor the moisture might not have evaporated as quickly with the result that there would have been a lot more mould growth.
To go back to Randy's original 'rant', FWIW I have used both PL300 and cheap latex caulking to glue foam together. The PL300 is inseperable. The cheap caulking came apart easily.
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
My contractor raised that point about my exterior door as well. My old finishing was the same - furring strips with paneling nailed to it. With a proper wall there, the door will be set into the wall a bit. But the door to the garage is already like that - on that wall, they used 2x3's with the paneling nailed on. Still no insulation or anything, so why that wall got thicker actual studs and the wall that really is an exterior wall got only furring strips, I have no idea. A lot in this house has me shaking my head - stuff that was hidden until the old stuff was all ripped out. Not just stuff in the basement, either, other things have been exposed and are nuts.
If the walls are in such bad shape that they can't control the environment then I suppose insulation in some form may be called for. Otherwise, why not just close up any cracks with an aforementioned product (or polyurethane caulk), seal, paint, and leave it alone.
I too am reluctant to punch holes in block on exterior wall for the purpose of anchoring anything to the wall - so I understand if a contractor feels the same. I just don't get the need for the foam to adhere to the actual block.
My framing for my backdrop will be supported by 2x4 screwed/bracketed into the bottom of my ceiling and/or floor joists so I don't have to put any holes in my exterior walls.
IMG_0634 by The Milwaukee Road Warrior, on Flickr
IMG_0633 by The Milwaukee Road Warrior, on Flickr
IMG_0635 by The Milwaukee Road Warrior, on Flickr
In Indiana, I believe the frost line is 30 inches. Since at least 1997, many builders will insulate the top half of the sunken basement walls, but not the bottom half. I think its a best practice there, but not a strict code.
They place fiberglass insulation directly on the concrete and attach it with big washers and fasteners, then wrap that in a vapor barrier. It results in a 4 foot wide strip of useless ugly fiberglass around the top perimeter of the basement.
I concluded that if the insulation actually functioned for the top half of the basement wall, there would be a condensation problem, which would seem to be an issue with fiberglass directly on the concrete. I'm no expert, but it seemed very odd.
We tore it down almost immediately, plastered up the holes and other imperfections in the concrete and painted the walls with moisture resistant primer (as a precaution) then a tannish gray. We had no problems at all with condensation from excessive frozen winters or even noticed a temperature difference.
I'm assuming Randy's contractor is using rigid foam instead of the fiberglass and attaching it with adhesive rather than big washers and fasteners. There is probably a good reason for that since the basement is partially exposed.
- Douglas
I am also involved in construction and engineering for my work, and in the past I did work that involved energy conservation at a lot of rural farmhouses in Iowa. Spent a lot of time under them insulating nasty crawlspaces and blowing cellulose insulation into 100-year old walls that had no insulation whatsoever.
I confess I am at a loss to understand why the foam would NEED to adhere to the exterior wall. If anything, I would think that a small air gap between the block and the foam would serve as a sort of thermal barrier - similar to argon-impregnated window panes in many modern replacement windows. The surface variations of concrete block would make it impossible to get any good tight bond between the block and foam I would think.
Concrete block will sweat anyway, its just the way it is. Vapor pressure pushes moisture thru the block. So it seems that you will eventually get moisture between the block and the foam no matter what you do. My concern is always what happens with the moisture once it is in that annular space: if there is no air movement in there it will have no way to dry out, which can lead to other problems. Interior air quality is a huge problem for so many homes...
My 2 cents.
All the drainage on my house was badly neglected. The gutters were the original jointed type, and the joints were almost all leaking, droppign water all along the rear of the house (on the front, it was out past the porch, and also down hill, so what did come down in the wrong place always ran away from the foundation, and the rest was in front of the garage, which ran down the driveway and not back into the house). There is a later added roof over the patio, but it stopped about 2 feet short of the one corner of the house, so there was a tiny section of gutter with its own downspout, that dropped straight down in the corner of the house. On my plans I've posted, it's the top right corner. Guess where the worst water penetration was on the block, and the worst mold on the old walls when they were ripped out was? On top of that, the downspount fromt he patio roof dropped water right int he corner of the patio, which was getting undermined. The patio was coated with a layer of cement with a brok pattern, but the undermining cause the two slabs to settle differently and there are big chunks of it all cracked out now. I'm going to have to chip it all off, and either just have a plain concrete patio, or have that done over again. With the new gutters, water only runs off through the downspouts, and the two problem ones were extended out to keep the water away from the house. On the garage side, there is actually a pipe alongside the house that exists into the driveway, why this wasn;t done on the other side of the house, I'll never know.
Plus they made a mess of things when they put the pool in, the whole yard slopes right to the back of the house. The removed dirt was piled on the hill outside of the fence, then the pool area is flat, then a down slope to the house. The pool deck is about 2 feet higher than the ground level at the foundation. We put in stone edginf along both flower beds to either side of the patio and filled it all in to make them raised by about a foot, combined with water fromt he roof no longer dropping right along the foundation edge, this has stopped the water seeping in (never puddled in the basement, just kept the block damp). There has never been standing water int he basement, no evidence of it from the past (no stains under the carpet after it was removed), and nothing in the nearly 6 years I've been there. And we've had plenty of heavy rains where it filled up and actually oveflowed the pool. So I'm pretty confident that the issues are all solved, finishing the walls will only make it even better. At the height of summer humidty, I got a dehumidifier, starting humidty was around 70%. The single 50 pint rated dehumidifer I got was able to reduce and maintain it under 40% with no problem - running idle most of the time after the initial period of drying things out.
IMG_1323 by The Milwaukee Road Warrior, on Flickr
This entire corner of my basement block wall was basically covered with staining of various shades of brown, black, and gray. The problem downspout was right at the corner where the two exterior walls meet, to the left of the window. This side of my house has a driveway at window level (about 3' above the basement floor).
York1 John
I took a slightly different approach. I had a similar issue in one corner of my "bi-level", where previous owners just let a downspout discharge right at the foundation. I know this is shocking, but this caused water damage below on the block wall! I know, right?!? I put in new gutters and downspouts with extensions.
Anyway, it took me a long time but I ripped out the old paneling and wood in that part of the basement and spent a lot of time cleaning the block. I never had the block tested, but it definitely had efflorescence and mildew on it. After treating I sealed any small cracks with DAP concrete filler and coated it with 3 coats of Zinsser WaterTite paint.
Although it is more of a pain for model railroading, I refuse to finish my basement. After a number of years of work I'm back to the bare block walls, which have all been painted. The exterior walls are all sealed with WaterTite. My thinking is that if there IS an issue with either cracking or mold growth, and I have everything behind drywall and/or insulation, I won't know -- not until it becomes a BIG issue.
Right now I'm working on building a 2x4 frame of sorts on which to mount my layout backdrop (definitely more difficult than just being able to attach my hardboard right to a drywall wall), but I will still be able to monitor the condition of my exterior walls and deal with problems early on.
davidmurray Here in southern Ontario, and many northern States in the USA the winter frost line can be as much as 4' deep. For this reason building codes here specify insulating 4' below grade, or to the floor, which ever is less. Foam doesn't absorb/retain water the way batt insulation may. Vapour barrier should go on the winter warm side of insulation. Building methods are improved over time, and regional needs vary. Dave
Here in southern Ontario, and many northern States in the USA the winter frost line can be as much as 4' deep. For this reason building codes here specify insulating 4' below grade, or to the floor, which ever is less.
Foam doesn't absorb/retain water the way batt insulation may. Vapour barrier should go on the winter warm side of insulation.
Building methods are improved over time, and regional needs vary.
Yes, they vary quite a bit by region, Randy and I are in the Mid Atlantic, were the 100 year frost is only 24". Foundations are only required to be 36" below grade, and vapor barriers are only needed/used in some situations.
I am a historic restoration consultant and residential designer by trade. Codes are often created to suit a number of political and social goals as well as health and safety.
And the risk/reward of making a building too "tight" is still up for debate.
My house is definitely not a split level, I grew up in a split level. Half basement, half flight up to level with laundry and family room, another half flight up to kitchen/dining/living over the basement, another half up to master bedroom, one extra bedroom, and the bathroom over the family room, and another half flight up to what ended up being th ebiggest bedroom (mine) over the kitchien/living/dining.
My current house is a true raised ranch, set in a hill. all living quarters are on one level. Underneath is the basement and garage, I'd have a HUGE basement if not for the garage being fully under the main level, it's an extra-large garage, 2 cars+ wide, and 2 cars deep. Except for the wall between the basement part and the garage, and the front entry door, it's all below ground except the upper foot maybe of the basement walls.Only good thing they did witht he design of this house was make the basement walls exactly 8 feet high. Each stud has to be trimmed to fit between the header and sill plate, but the foam sheets go on as-is, and so will the drywall.
ANd yes, they are going to install and tape the drywall. They would paint it, too, but my GF was like "we can do this in a weekend" so it took a significant chunk off the price, but I am holding her to it - the walls need to get painted before they can hang the drop ceiling and finish the job, so the longer it takes to paint, the more delayed the whole project is.
Tasks that I am keeping DIY include getting all the staples (from the old carpet) out of the stairs, sanding and painting said stairs, and installing hand rails.
I've seen that done, with a raised ranch, where close to 4' of the wall is not underground, putting insulation against the wall, then a frame wall in front of it.
We also call those bi-levels, or split levels, where 4' of the basement is buried, and the top 4' is exposed.
My daughter's is built that way, walk in the main entrance, and go down 6 steps to the basement floor, or up 6 steps to the main living area.
We furred out and insulated the entire lower level, from the basement floor to the ceiling, taking particular attention to the sill area.
Are your contractors going to hang and finish the drywall, ready for you to paint?
Mike.
My You Tube
How is it easier to run wiring with fiberglas? The stud vacities are completely open and free for wires to be pulled, the foam is behind the stud wall.
Yes, it's a partial walkout (raised ranch, one wall is the garage wall, and there is a narrow front with a door into the basement next to the garage. Rest is underground.
Moisture source was taken care of a few years ago with new gutters and downspouts to replace the leaky old (original) jointed ones. Walls were treated before installing the foam.
Guess I am most used to fiberglass insulation bats with the paper facing - the paper certainly is a mold haven.
ATLANTIC CENTRAL Well, just my view, but if you have moisture, you will end up with problems with mold on framing and drywall no matter the type of insulation. Vapor barrier between the masonry and framing is one way to protect against that. Not sure I understand what the wiring has to do with insulation, except that wiring is easier with fiberglass? Is the basement a walk out or fully below grade? While current new construction codes require basement insulation, I'm not a big fan of too much insulation in basements completely below grade. They are already 55 degrees or better all year long. Insulating the sills is way more important than the walls.... Sheldon
Not sure I understand what the wiring has to do with insulation, except that wiring is easier with fiberglass?
Is the basement a walk out or fully below grade? While current new construction codes require basement insulation, I'm not a big fan of too much insulation in basements completely below grade. They are already 55 degrees or better all year long.
Insulating the sills is way more important than the walls....
Agreed. The walkouts should be insulated, at least the outside walls.
Totally undergrade doesn't need insulation since its 55 degrees anyway. Just a dehumidifyer and a heat duct takes care of summer and winter, IMO. Our previous "finished" basement in Indiana, we simply painted the poured concrete walls and ran some conduit for a couple of electrical outlets. Used plaster to fill in the little voids in the walls. It had that industrial look to it, but very comfortable year round. The train room required building separate backdrops, which don't look as nice as fiished walls.
If the layout is going to occupy the entire basement, I certainly see why wanting finished walls would be desired.
Not sure why attaching foam to the walls is the preferred way.
mbinsewi When pointed out, some would add more bark chips, or decorative stone, thinking they "raised the grade" and fixed the grade/down spout issue. Wrong. Mike.
When pointed out, some would add more bark chips, or decorative stone, thinking they "raised the grade" and fixed the grade/down spout issue.
Wrong.
We just bought a house this summer and the sellers lost out on a good $20k because of a couple hundred bucks worth of down spout extensions.
rrinker If there is, it's very little, they built this tight, on the two walls they have up so far. Where there's any chance of moisture - regular insulation bats will mold and mildo. Foam won't. Also thought of somethign else - half the electrical outlets will be installed high, so power supplies and such for the upper deck will be able to sit on the top of the upper level valance, instead of having cords snake through everything. Plus that gives a perfect break for the dual circuits - upper level and lower level. --Randy
If there is, it's very little, they built this tight, on the two walls they have up so far.
Where there's any chance of moisture - regular insulation bats will mold and mildo. Foam won't.
Also thought of somethign else - half the electrical outlets will be installed high, so power supplies and such for the upper deck will be able to sit on the top of the upper level valance, instead of having cords snake through everything. Plus that gives a perfect break for the dual circuits - upper level and lower level.
Well, just my view, but if you have moisture, you will end up with problems with mold on framing and drywall no matter the type of insulation. Vapor barrier between the masonry and framing is one way to protect against that.
BigDaddyMy basement wall developed micro cracks because the drain spouts dumped their water next to the foundation. When I fixed that, the leaks stopped.
When I was doing home inspections, that was the wet basement problem, probably 95% of the time.
Mold and mildew are fungus. I suppose fiberglass gives them more surface area to grow but they don't need either foam or fiberglass for the nutrition.
My basement wall developed micro cracks because the drain spouts dumped their water next to the foundation. When I fixed that, the leaks stopped.
Henry
COB Potomac & Northern
Shenandoah Valley
ATLANTIC CENTRALBut it always has voids between it and the framing.
Since my walls are covered with sheetrock, I can't say for certain, but the few walls I have modified over the years showed the foam was wedged so tightly in between the studs that I had to break some of it to get it out.
My basement is not damp, but I wonder if the foam was used because some basement walls are damp.