New house questions

[dave1949]

I am not trying to scare anyone, a properly done slab should last a long time. I believe the problem lys with poor construction methods. Friend of mine wanted to get an equity, house{double wide} was around 8-10 years. They wanted him to put block around the house 1st{instead of the skirting}. When he did this he found his slab had shifted allmost 1 foot from one end to the other{long home}. Another guy I know from down south had his house{stick built} on a slab for 20+years. Started having some plumbing issues, checked it out and found out the slab had cracked in one corner and started dropping everything. Another guy had his house{double wide} for a year toilet backed up, slab shifted messing up plumbing. There are many more of these stories but I don't want to panic or start a B fest with anyone. If you are doing a slab just make sure it is done right. Even a little shift in a slab that causes plumbing problems could easily turn out to be much worse down the road.

Foundations can be very frustrating and much of how they work relys on the ground their in. I say every situation is different and if it were me having a foundation put in, the foundation contractor better know something about the earth{dirt, sand, clay, rock, etc} AT MY BUILDING spot. Up here I can go from clay to swamp goop to sand to rock all in a very short distance. What may work for 1 would fall to pieces on 2.

Okay, I see the sort of problems you are talking about. They aren't uncommon, but like you, I believe they can be overcome with proper construction for the locale to start with. Foundation work can be frustrating for sure. Mostly because you only get one chance to get it right, after that is becomes a very expensive problem - except for that 100 yr old stack rock foundation Jack it up and stick a rock in. Does have a certain appeal to it.
Dave.

 

[boxygen]

Dmccarty is right, Lstiburek knows his stuff. He essentially started the "building science industry." He is recognized in the building industry as an expert. Hes not just a builder with an opinion, there's plenty of those around. Also, if you ever have a chance to see him in person, he is extremely interesting and very entertaining too in his presentations.
I work as a project manager for a company that builds 5-6 multi-million dollar houses per year. All of them are 100% custom. We have to keep up on building science, or we will be left behind and stuck with VERY expensive warranty calls. Its getting harder and harder for the average homeowner to fully understand their building components and how they all integrate into a system and mini environment.
I recently turned down a job for a homeowner that wanted to winterize her crawlspace in an old farmhouse. She thought it was as simple as stuffing some fiberglass insulation in the joists (logs). What she really needed was about $30k in work to address all the issues related to truely making that dry conditioned space. I have a good relationship with this client, but I think she thought I was trying to take advantage of her. I couldnt do the job unless It was a comprehensive approach. A few days later I attended Weatherization Seminar held by two other distinguished building scientists that was sponsored by the Maine Indoor Air Quality Council. There was an extensive write up on the front page of the local paper the next day by a reporter that attended the seminar. It outlined everything that I told her and the liabilities and severe problems that can be caused by not addressing the entire building envelope as a system and managing air quality, and moisture properly. I mentioned it to my client and she said he had already read the article. She finally realized I wasn't blowing smoke, but she still was disappointed and didn't have $30k.
Houses have changed much like cars have in the last 30 years. 30 years ago cars were a lot easier to work on by the average person and could get by with much more marginal repairs and still function properly. Anyone could slap together a house with simple builidng materials and due to cheap energy and leaky assemblies, not many problems happened. When assemblies became more complex as did material choices, problems started to happen. Read the book that pertains to your particular climate because cold climates are very different than warm climates when it comes to building techniques.
I could give you tons of advice on what to do and what not to do but after about a six pack, we only would have scratched the surface, and most importantly, it all depends on your certain wishes, and site conditions. The best advice I could give is spent plenty of time educating yourself and use this education to find the proper builder. Check references, see how enthusiastic they are about your particular project and the challenges it presents and how they plan to address those challenges and balance it against what you want. Go with a builder who knows what they are doing and you enjoy working with, not the lowest bidder. You get what you pay for. Just my two cents.

 

[eepete]

@dave1949: I know someone who built a house and the crawl space is interior space. It has a 1.5" concrete floor, a drain just in case, and the block wall is sealed and insulated. Pretty sure he had metal termite barrier on the top of the block, with the understanding that this just reduces the chance of having termites. The goal is to keep everything dry. So far so good, but it's a new house.
Our 1st house had a open to outside crawl space, never again. Plastic helped, but it was a muddy musty buggy mess. We had a blow-up snake to supposedly keep birds out of the garden, tossed in there for the winter. We should have told the termite inspector that, never saw someone exit a crawspace so fast. Live and learn.

My basement is a slab (walls are Superior walls). Where the PVC drain pipes come through, they are wrapped in foam so the slab can move a bit without dragging the pipes.

Our house has good solar design with regard to orientation, overhangs, and window placement. But it is a low thermal mass so that forced air can control the temperature (geothermal heat pumps).

boxygen says it all for me. You have to spend a lot of time learning, talking, and figuring out what's important to you. Not too different from buying a tractor, it's just that the decimal point is shifted over a place or two.

Pete

 

[Alan L.]

If I were to build another house, I would insulate the roof with foam, that is, make the entire house an envelope. When we built our house, after much research, we ended up using foam in all the walls, in all cathedral ceilings where the roof in on top and the ceiling is on the bottom of the rafters, and under plywood walkways on top of flat ceilings. We went with ridge vents and radiant barrier, and R8 ductwork, plus R50 blown fiberglass everywhere else.

The house is pretty energy efficient, I think very efficient although I don't get these $60 election bills like some because we keep it COOL in the summer.

But if I had to do over, I would insulate the entire envelope - the roof and everything, which of course would then not be ventilated. There are several reasons I'd have spent another $4K to do this. Number one is the attic space becomes clean and accessible. You can't walk around in 24" of fiberglass. Number 2 is that in 2.5 years mice have rearranged the insulation and there are tunnels everywhere. And although the radiant barrier and the ventilation work very well (attic temp stays about what the outside temp is during the summer), that can still be hot and stuff for servicing A/C units etc.

Those areas in the attic where I made a store-room etc are very comfortable and so much nicer than the other areas. I feel like I made a mistake and at some point someday I might retrofit it with foam.

Go with the foam and full envelope. Its great.

 

[dave1949]

@dave1949: I know someone who built a house and the crawl space is interior space. It has a 1.5" concrete floor, a drain just in case, and the block wall is sealed and insulated. Pretty sure he had metal termite barrier on the top of the block, with the understanding that this just reduces the chance of having termites. The goal is to keep everything dry. So far so good, but it's a new house.
Our 1st house had a open to outside crawl space, never again. Plastic helped, but it was a muddy musty buggy mess. We had a blow-up snake to supposedly keep birds out of the garden, tossed in there for the winter. We should have told the termite inspector that, never saw someone exit a crawspace so fast. Live and learn.

My basement is a slab (walls are Superior walls). Where the PVC drain pipes come through, they are wrapped in foam so the slab can move a bit without dragging the pipes.

Our house has good solar design with regard to orientation, overhangs, and window placement. But it is a low thermal mass so that forced air can control the temperature (geothermal heat pumps).

boxygen says it all for me. You have to spend a lot of time learning, talking, and figuring out what's important to you. Not too different from buying a tractor, it's just that the decimal point is shifted over a place or two.

Pete

LOL on the blowup snake. As far as house building, I am like Sitting Bull at this point, 'I shall build no more, forever' I do have an interest in the topic and try to keep up with new techniques and materials. I did a lot of studying on it before we built and quizzed people locally about how and what worked for them. That was only 5 years ago and things are moving on already.

I had a crawlspace many years ago. Never had any issues except the time I had to go to Phoenix in early winter for several weeks and forgot to put the vent covers on. Saw on the news what a terrible cold snap was back home. Figured I better call. 4 yr old son answered the phone. Asked where is Mom? Under the house - it hit me in a flash that I had forgotten. Some pipes were freezing. Not one of my better moves. You can feel like a real dope sipping margheritas poolside while your wife tries to thaw pipes

I wouldn't choose to have one again, especially in the north. Like you say, musty and buggy. The heating I think would change a good bit with a sealed and insulated crawlspace. Sort of counter intuitive that something you think of as musty and buggy becomes conditioned space. It sounds like it could work, I would be monitoring it closely for several years though for condensation, mold, etc.

We don't have to fight termites here very often, do have to keep an eye out for carpenter ants. They at least have the habit of crawling around out in the open during summer. Track them back to their nest area and they are pretty easy to kill off.
Dave.

 

[dmccarty]

Dmccarty; Just curious how long have you been on your slab? The reason I ask is because I have known of a couple of homes that sat great for some time{20yrs} with no trouble, THEN...... all poo hits the fan? I hope you have great luck with your slab, and enjoy the fact that there are so many different routes one can take for a foundation.

The current house is only five years old. Our old city house was about 30 years old. My grandmother lived in a slab house for close to 40 years. My parents have lived in various slab houses that have had to have been 20-30 years old. Lots of family members have lived in slab homes as well. I can only think of three non slab homes lived in by various family members. Crawl spaces much less basements are just not built where my family has lived.

A house is going to give you problems. I see more problems with crawlspaces and basements than slabs. My neighbor's crawl space is very wet. I don't know if he has fixed it, but if he has not, he has a huge time bomb. Its not going to be a fun or cheap fix. Before they bought the house I looked into the crawl space and it was dripping wet from the house structure. Mold was already starting.

If the slab is a problem it really is because of bad construction.

I know if our old city house had a crawl space I would have been replacing the wood floor in the bathrooms from toilet leaks. Plus insulation problems due to the leaks. A coworker had to rip out the tile floor in her less than 5 year old house due to water damage from the leaky toilet.

Our slab could be problematic at some point. But most likely it won't be. A crawlspace I know would be. A toilet WILL leak. And it WILL get stopped up and overflow.

Later,
Dan

 

[20 20]

I keep seeing the termite issue and just want to add something. Termites DON'T allways come from the ground up . I did research on this when I was building and found that many infested homes had termites that actually started high up. Of course if they have a direct connection from ground to wood then they'll take it.

 

[20 20]

The current house is only five years old. Our old city house was about 30 years old. My grandmother lived in a slab house for close to 40 years. My parents have lived in various slab houses that have had to have been 20-30 years old. Lots of family members have lived in slab homes as well. I can only think of three non slab homes lived in by various family members. Crawl spaces much less basements are just not built where my family has lived.

Thanks for your reply, like I wrote just curious

A house is going to give you problems. I see more problems with crawlspaces and basements than slabs.

And I can say just the oposite, different events conditions etc come into play, neither is wrong or right.

My neighbor's crawl space is very wet. I don't know if he has fixed it, but if he has not, he has a huge time bomb. Its not going to be a fun or cheap fix. Before they bought the house I looked into the crawl space and it was dripping wet from the house structure. Mold was already starting.

I agree he must not have good drainage, he should definately fix the problem. To fix the problem it may be easy or hard, no way to tell without seeing it.

If the slab is a problem it really is because of bad construction.

Agreed but sometimes proper construction may be a much higher bill then piers, that could work better???? Once again foundations are tricky and without knowledge they can make or break the bank and the house.

I know if our old city house had a crawl space I would have been replacing the wood floor in the bathrooms from toilet leaks. Plus insulation problems due to the leaks. A coworker had to rip out the tile floor in her less than 5 year old house due to water damage from the leaky toilet.

Are you saying it's okay to have a leaking house on a slab, but not on a crawl space? Sounds to me the problem would the leak, which in the end result would have nothing to do with the foundation?

Lets say your slab shifts and breaks the main septic line{line is in the cement}. Now lets say your main septic line breaks in a crawl space. Which one is truely easier to fix???
If your toilet is leaking then I'd suggest fixing it no matter what your house is sitting on

Our slab could be problematic at some point. But most likely it won't be.

I hope it never is, but anything man made can be a problem at some point

A crawlspace I know would be.

There is no way you'd know unless you are on a crawl space, that statement is hearsay without any fact

A toilet WILL leak. And it WILL get stopped up and overflow.

Later,
Dan

I agree toilets will give a head ache, so we fix the toilet. Comparing a toilet to a foundation is like comparing a car to a monkey.

Lets say the toilet leaks and causes the floor in a crawl space to be ruined. It still isn't that bad of a fix{I've done a couple over the years}. Some new wood tile{whatever} problem fixed, usually not very exspensive. Now lets say your toilet sits on the slab and the pipe breaks inside the slab. MAJOR job is the easiest way to put it, busting up cement finding the break and then the repair.

 

[luscsmith]

Thank you all!! I went to the building science web site and my oh my how things have changed. In a hot humid climate the stud walls, ceiling and rafters are not insulated and the attic is not vented. The whole house is covered on the outside with 2 inches on walls and 4 inches on top of the roof deck. This process is to stop the thermal transfer of the studs and trusses.

I am still researching now more than before, Scott

 

[herd]

I keep seeing the termite issue and just want to add something. Termites DON'T allways come from the ground up . I did research on this when I was building and found that many infested homes had termites that actually started high up. Of course if they have a direct connection from ground to wood then they'll take it.

That may be true but, they have to go to ground for water. That is why you termite treat the foundation, and not the attic.