Hi,
I’m a mechanical engineer and I’m planning a new home that has a garage under the house. The land begins level with the garage floor at the front, and slopes up gradually until it is 6 feet deep as you go the rear of the house. I want to put a thick (4″ to 6″) granite stone veneer on the first level to cover the exposed foundation where it is visible. I don’t want to bury any expensive stone when I backfill the sides and rear of the house, so I want to step the supports for the stone veneer as I go up the slope. However, I’m not sure how to accomplish this easily. I’ve considered making steps in the foundation, but that seems like a lot of extra work and expense when making the forms and pouring the concrete, because the foundation needs to be 6″ thicker everywhere below the veneer in order to leave enough foundation wall thickness (8″ to 10″) behind the veneer to be self supporting up to the the first floor level — so I would end up with a lot of 14″ foundation! I’ve also considered bolting angled aluminum to the finished foundation wall wherever I need a step, as well as making a rebar- reinforced concrete shelf that sticks out of the foundation wherever I need it. I’ve attached a jpg of the house design and the stepped foundation that I’ve started designing so you can see what I’m trying to do. Does anyone know how this is typically done? Thanks, Paul
Replies
2Paul,
Make your footings wide enough to carry the stone. Angle will flex and then as frost heaves it will force the veneer off the wall. If you are using ICF's simply get brick ledge and install it below the frost line.. below the brick ledge pour crushed rock. as a support. brick ledge is 4 inches wide so to cover where stone is 6 inches thick use crushed rock for an additional two inch support..
When you back fill, take some old pallets, nail a sheet of osb or plywood etc. set on top of brick ledge and back fill packing the dirt to use as a cheap form.. lift up the pallets, pour the concrete and you're ready for stone..
Hopefully you are going to use ICF's ! they are simple and fun. Remember leggos? about that hard!
Hi Frenchy,
Thanks for the tip. I've read about ICF foundations in the past, but I've never seen one here in New England, so I didn't investigate it. I found the Quadlock ICF webpage and it looks like the system with the brick ledge would work. The only drawback is that I would need to schedule a separate concrete delivery for each level of step that I plan to make in the brick ledge.
Thanks,
Paul
2paul,
Not true! you pour the lower wall and then go back and pour the next step, etc.. The concrete sets fast enough that while you might have an extra hour or so in the pour you can do it all at once..
If you are really worried some ICF contractors will cap the lower sections (very easy to do) while they pour upper sections..
PS you pump not pour! don't even think about using a cement truck without a pumper..
you've already got the right idea. the brick (or stone) shelf is formed with the wall using either wood or styrofoam.
yes, the wall does get thick. here is a link with sketches. look at #2 not #1.
http://www.bia.org/pdfs/Supporting%20Brick%20Masonry.pdf
aluminum and concrete don't do well together. (corrosion) you could do the same with a steel angle, but if the steel corrodes, the stone falls off of the wall.
the shelf can be from a few inches tall to a few feet.
i would recommend talking to a local architect for some help with these details. the architect should also be able to help ensure that your design is within your budget before you spend many hours completing it. talking with a builder about this would also be a good idea.
carpenter in transition
Hi Tim,
Thanks. I didn't like the idea of using the aluminum bracket much either. I've seen those brick ledge detail drawings before, but all assume you allow the foundation wall to add the full thickness of the shelf for the full depth all the way to the footing. The question is, will it be more expensive to use all the extra concrete, or to spend more on labor making fancy forms to make several protruding brick ledges that step up as I go along the slope?
Thanks,
Paul
If it is just that small part of the foundation, from the bay bump forward, you might consider a wide-enough footing there, and an addition of 4" CMU (block) up from the footing to where your stone sets.
One of the good ICF sites for documentation is Logix.
What software are you using? Your design from scratch?
Gene,
Thanks. The problem is really in the back, where the stone veneer shelf starts much higher (6 feet above the footing), requiring either a 12" to 14" thick concrete wall below, or using concrete block to build up to that level.
The house was drawn in Chief Architect, and the foundation was drawn in SolidWorks. It's all from scratch, designed by me. I hired a designer who uses Chief Architect because I have not used it before. I just use Solidworks. I've included another image of the house.
Paul
Hi Paul,
What we have done in the past is to use a wider footing then lay up a CMU block wall below grade. Cap it off with the finished stone veneer above grade. One word of caution, taller masonry veneer walls facing a poured wall require the use of dovetail slot anchors (consult your local code). I'm not sure how the use of ICFs effects this.