Bricks, Masonry, Asphalt and Concrete - New addition to house
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ausmith
03-30-07, 01:08 PM
This summer I am planning on adding a new room to my house. This is going to be a workout room and we will access the room from the garage. Where I live there are no building restrictions and I dont need any building permits. In the past I have helped with building a garage and added a front entrance to a house. With that being said I do need to get some information concerning the foundation of the room I plan on building.
The pad for the new room is going to be level with the pad in the garage. On the other wall of the house the pad will be about 2 foot lower than the first floor of the house which would put it up to the concrete block wall of the basement.
The room size is going to be 11 x 17. I know that I need to make the pad slightly larger than the house addition and have already figured that into the pad size. Since this room is going to be added to my existing house do I have to connect the pad to the existing foundation or can I just pour the concrete right up to the block wall?
I am planning on digging out about a foot or more of the existing soil so I can backfill it with gravel. On top of that I am going to place some 6mm plastic and then put some 2 ridged foam insulation. Then I will be putting in the screening and rebar. Around the perimeter of the foundation I am planning on going down another 6 x12 wide for the footer. The pad thickness is going to be 4 which should be around 3 yards of concrete.
This room will be attached to the existing house on two sides so I only need to build the two exterior walls. I am planning on removing the siding on the house and reusing that on the outside of the addition where possible. The exterior walls are going to be 2x6 and the interior walls will be 2x4.
Does it sound like I have everything figured out or is there something that I am missing?
Thanks for any help.
The pad for the new room is going to be level with the pad in the garage. On the other wall of the house the pad will be about 2 foot lower than the first floor of the house which would put it up to the concrete block wall of the basement.
The room size is going to be 11 x 17. I know that I need to make the pad slightly larger than the house addition and have already figured that into the pad size. Since this room is going to be added to my existing house do I have to connect the pad to the existing foundation or can I just pour the concrete right up to the block wall?
I am planning on digging out about a foot or more of the existing soil so I can backfill it with gravel. On top of that I am going to place some 6mm plastic and then put some 2 ridged foam insulation. Then I will be putting in the screening and rebar. Around the perimeter of the foundation I am planning on going down another 6 x12 wide for the footer. The pad thickness is going to be 4 which should be around 3 yards of concrete.
This room will be attached to the existing house on two sides so I only need to build the two exterior walls. I am planning on removing the siding on the house and reusing that on the outside of the addition where possible. The exterior walls are going to be 2x6 and the interior walls will be 2x4.
Does it sound like I have everything figured out or is there something that I am missing?
Thanks for any help.
Concretemasonry
03-30-07, 01:26 PM
You have one area to concern your self with depending on your climate.
If you have frost, you could end up with a problem connecting a slab on grade addition to a house that obviously has the foundation below the frost line. This could lead to frost heaving of the addition, which can rack your house slightly, leading to possible wall cracks and roof leakage problems.
Sometimes you can get away with a garage above the frost, but that is usually an extension and there is only one wall connected to the house.
Code or no code, frost heaves and the 2" rigid insulation could lead to colder temperatures under your thickened edge "footing" which could increase the heaving.
If you use a shallow footing for the addition instead of block below frost, there is a concept of shallow insulation that could be applied. This involves extruded polystyrene used vertically and horizontally out from the addition.
Dick
If you have frost, you could end up with a problem connecting a slab on grade addition to a house that obviously has the foundation below the frost line. This could lead to frost heaving of the addition, which can rack your house slightly, leading to possible wall cracks and roof leakage problems.
Sometimes you can get away with a garage above the frost, but that is usually an extension and there is only one wall connected to the house.
Code or no code, frost heaves and the 2" rigid insulation could lead to colder temperatures under your thickened edge "footing" which could increase the heaving.
If you use a shallow footing for the addition instead of block below frost, there is a concept of shallow insulation that could be applied. This involves extruded polystyrene used vertically and horizontally out from the addition.
Dick