I am planning on finally getting out of the city and starting on my long term home.  I have been researching ICF for the past few years and about a year ago started designing an ICF house in which I can raise my children.  Anyway, I have started getting bids to make sure I can afford it and have run into the question whether or not I should try to complete my entire daylight basement with 8" block all the way around.  Currently my draftsman used 8" block for about 2/3 of the way around where it retains fill and then switched to 6" block for the remaining 1/3 where there is no backfill.  I recently talked to one of the ICF contractors who bid the job and asked him whether I should consider using 8"block for the entire basement and he said I could keep it the original way because of my budget but if it were his house he would use the 8" for the basement which would give a nice ledge for the floor joists and I would not have to hide 2 transition points from 8" to 6" where the walls changed.  There were also benefits such as sound deadening and thermal mass which is very important.  I have not received the difference in cost yet but was wondering if anyone has had to make this decision and why they chose it?  These plans have not been engineered yet which may solve my problem but I am trying to see if I can afford it first in case I have to change back to a wood framed package.
My second question is trying to find the best waterproofing  for the basement.  I have read some horror stories and want to avoid them.  I live in Western Oregon which is wet for 7+ months but has a fairly moderate climate.  I am leaning toward a 2 step waterproofing with either a spray or stick on membrane with a dimple board on top.  Is spray on or peel and stick better?  Dimple board?  Suggestions?

Sorry, 1 more.  Form-a-drain worth the cost or not?

Thanks,
Ryan

I'm curious - why have a underground basement vs a frost protect shallow slab with a "fully exposed basement/garage" if you need that type of space? Thermal mass isn't the big benefit that you may think it is.

Currently my draftsman used 8" block

Is there a reason you can't go with 6" block all around?

Is spray on or peel and stick better? Dimple board?

I think peel and stick is better with ICF because it provides an unbroken water barrier. It is more labor-intensive than spray-on, however.

Once you have the peel-and-stick, the dimple board is just over and above unless you have difficult soils or obvious water issues like having to site the house in a low area. If your soils are well-drained, it's less likely you'd really need the dimple board. Or, if you wanted to go through the effort of making sure the foundation is backfilled with a well-drained curtain of gravel, that would lessen the necessity for the dimple board. If you wanted to just backfill with local clay soil, I'd go for the drainboard with the attached geotextile.

Make sure your roof drains are conducted well away from, and lower than the house site. I'm always surprised at how many people think two or three feet away is sufficient. A lot of water comes off the roof.

I spec'ed Form-A-Drain, but the contractor resisted because of unfamiliarity. In retrospect, we should have used it. Didn't make much cost difference for the foundation contractor, but I would have saved a huge amount of cost and labor on my part setting up the footing drains. A huge amount.

Bottom line is that if you are aware of and worried about drainage issues, the cost and effort of putting in quality drains up front is more than worth it for the protection and peace of mind.

Not sure what a frost free shallow slab is?  I have a south facing slope which makes it perfect for some passive solar and the walk out daylight basement that works with the property orientation and slope.

I have not had the plans engineered yet so I am not sure I need 8" block around the basement.  I do live in the pacific northwest and on a slope so the combination of earthquake danger and amount of backfill that this basement will hold back will probably need a 8" block.  Not sure though.  The question is if the engineer calls for an 8" block, am I better off having 8" all the way around the basement or saving some money and transitioning to a 6" block where I do not have fill.

My worry with form a drain is that I assume like a traditional drain, it can plug up over time.  It is already a premium add on that I have not budgeted for and is it really worth the money?  If it plugs up some day I will still have to dig it up and add a traditional footing drain.  It cannot be replaced since it is attatched to the footings.

Thanks

It cannot be replaced since it is attatched to the footings.

Done right, it won't plug up any differently than any other product and probably less so because it should be continuously level with the footing and free of dips and rises that you can get with other footing drains.

If it does plug, you can just lay new drainpipe outside it as you might do for any other. Water will still take path of least resistance.

I do live in the pacific northwest and on a slope so the combination of earthquake danger and amount of backfill

How much extra backfill? I had total height backfill with a full basement in the PNW that was engineered to above-code standards. It was 6". Make sure you include some jogs or bumpouts in the foundation. Maybe even use ICF for an interior wall or two. The added complexity isn't much and it strengthens the walls over long, straight runs.

Posted By ICFHybrid on 03 Sep 2011 03:47 PM

It cannot be replaced since it is attatched to the footings.

Done right, it won't plug up any differently than any other product and probably less so because it should be continuously level with the footing and free of dips and rises that you can get with other footing drains.

If it does plug, you can just lay new drainpipe outside it as you might do for any other. Water will still take path of least resistance.

I do live in the pacific northwest and on a slope so the combination of earthquake danger and amount of backfill

How much extra backfill? I had total height backfill with a full basement in the PNW that was engineered to above-code standards. It was 6". Make sure you include some jogs or bumpouts in the foundation. Maybe even use ICF for an interior wall or two. The added complexity isn't much and it strengthens the walls over long, straight runs.

Full height backfill on two sides and partial on one other.  The back will be a full walkout.  Will have to see what the engineer says.  I definitely don't want to try to save alittle money and have a problem later.  Never thought about interior ICF walls.  Is that for support for the exterior walls?

Makes sense what you said about the form a drain but is it worth the extra cost?

Is that for support for the exterior walls?

Yes. And for function: wine cellar and temperature regulated storage rooms that are insulated from the other basement living spaces. They also support Insuldeck over the basement which allows for a radiant slab on the main floor as well.

but is it worth the extra cost?

If you are sub contracting the work, you'd have to bid out all the components on your job to compare, but in my case, where I did the drainage myself, the answer is YES, by a huge margin.

Roughly, on one side of the equation, you have the extra cost of the FAD over the form boards. On the other side, you have the labor to remove conventional form boards, labor for regrading the dirt after everyone has caved it in, labor for laying the drain pipe, and, of course, the cost of the drainpipe itself. Using the FAD would have also saved materials as far as respects silt barrier and drainrock.

What I've seen recently is that it is easy for contractors to skimp on footing drains, both in materials and quality as it is very quickly covered up and no one wants to dig back down there to verify.

Yes. And for function: wine cellar and temperature regulated storage rooms that are insulated from the other basement living spaces. They also support Insuldeck over the basement which allows for a radiant slab on the main floor as well.

I hadn't thought about it. I'd love to try insuldeck and have radiant throughout but I don't think budget will swing it. My wife would also like wood and some carpet on the main floor. I do like the idea of wine storage. I have a spot but just need to avoid radiant in that room. Thanks

Greetings.

Radiant barriers are ideal for wine cellars. They are super efficient and don't grow mold or give off fumes.

For the ceil you want to attach a single layer RB to the bottom of the floor. I believe with your sys that would be to foam. Use a spray on adhesive and run stripes. Press RB on, there will be some slight sagging. Run 2x2" furring strips and attach another RB run 2x3" furring strips and attach drywall or other. The btu/hr/sf should be about TWO. Furring strips should cross.

For the walls one layer of RB should enough. Attach to the surface of the studs and the 1x2 furring strips across the studs,. Drywall.

Do not do any thing to the floor as it will help cool the room.

My storage room is in the basement and even if I don't run radiant under that portion, won't it still warm it from the tubing running throughout the slab on the other side of the wall? Probably won't ever have enough money for an actual wine cellar anyway.

My storage room is in the basement and even if I don't run radiant under that portion, won't it still warm it from the tubing running throughout the slab on the other side of the wall?

No. If you don't insulate the floor in the "wine cellar", it will tend towards ground temperature. The radiant tubing only has the ability to warm the slab in the neighboring room out to about a foot or so. If you keep the tubing away from the wall, you should be fine. You can also situate the wine cellar in a corner where it shares more outside wall with cool dirt and less inside wall with heated spaces.

I'd love to try insuldeck and have radiant throughout but I don't think budget will swing it.

If you design right, I think it is very affordable. A yard of concrete covers like 70 sf to 100 sf. That's about $1/sf. I think the InsulDeck itself runs about $5/sf. The labor was really simple.

Once the concrete is poured, everything is done, including your radiant tubing, ready to get hooked up. You can even stamp or stain the concrete, or polish it for a finished floor.

How does Form-a-Drain drain water away from a footing, when the drain itself is completely level?
Concrete is a sponge. It will absorb moisture through its surroundings, and transfer that moisture into your basement.
The drain pipe should be below and away from the footings. Not two inches above the bottom of the concrete, where water is actually pooling.
Sure it will kill two birds with one stone. But that bird is still going to dump moisture on those footings for the life of the home

How does Form-a-Drain drain water away from a footing, when the drain itself is completely level?

All footing drains are installed completely level...or, they are supposed to be, anyway. Water finds the path of least resistance, which is the drainpipe connected to the FAD just like any other footing drain system. From there it goes to daylight or a sump where it can be pumped out.

The drain pipe should be below and away from the footings. Not two inches above the bottom of the concrete

Can you explain what you are referring to? FAD is used as the footing form, which makes the bottom of the FAD drain the same as the bottom of the footing. The PVC walls of the FAD separate the water from the footing as it drains away.