[jondor]

We are about to finish a renovation and my wife wants a patio that comes up near the
double doors that lead out of the new family room. The house has a brick exterior. The
family room side sits on a very good footing that I dug myself because the contractor
seemed incapable of understanding what a footing is. 12" block sits on the footing for
one or two courses and then eight inch block so there is a brick ledge for the brick to
sit on. If the patio comes up near the double doors, (I would keep it down to the
bottom of the brick soldiers under the doors) then behind the brick is the treated wood
double band and the treated wood 2 x 10 joists. My concern is the attachment or non
attachment of the slab for the patio to the house. It seems to me that I need to insure that
water does not seep through the brick to the double bandm, and that termites do not
come up between the patio and the house. A (seemingly) reputable civil engineer suggested
an expansion joint made of heavy duty oil treated paper or fabric. Normally you have
four to six inches of gravel under four to six inches of concete and then two or three inches
of flagstone on top of that. But the footing is low enough that either dirt or more gravel, or
more concrete would be required to bring the patio up to the level where the flagstone will
be laid. I guess in could put some veritcal rebar into the footing and extend it up into the
concrete to keep the footing and the patio slab moving together. So what I really need to
know is whether to fill the footing with gravel or dirt at the bottom and what kind of
material to use for the expansion joint between the house and the patio, AND wheter it is
a good idea to bring the patio up that high.

[skiberger]

Did you install a drain tile pipe along that footing? If not you may want to consider that then fill in around the pipe and footer w/ gravel the fill dirt from there. The drain tile will help prevent any ground water from undermining the footer.

If the soils and gravel are well compacted you can float the patio from the house. If not and there is a chance of settlement you can drill and install rebar horizontally in the brick and into the rim joists. Seal them with an apoxy. This way the patio will be connected. You can use a homosote expansion strip between the patio and the house.

As far as termites are concerned, have the soils in and around where the patio will go pre-treated.

The height shouldn't be a problem as long as there is a 7-8"(ish) step down