Sewer and Frost Line Question

[macgyver007]

Good Day All, I have just joined this Forum and Hope this is the correct place to pose My Questions.

First I will give you the situation.
I have a completed Home on a Single Building Lot. From the Back of the house I have about 10 Feet of Green Space and then there is a 30X30 Cinder Block 2 Story Garage. (Also Mine)
The House measures approx 22 X 70 Single Story with a Full Basement.
The Garage is Completely Above ground with a Poured Concrete Floor.
The Garage is furniched with a Forced Air Natural Gas Furnace completely seperate from the house.

The Plan
I would like to Finish the second Story of the Garage and turn it into a Bachalor Appartment. I already Have Gas and Electricity fed to the garage. In order to complete the job I now have to get water and Sewer out there.

The Questions.
the closest Place where I can get access to my City Sewer is approx 25 Feet from the front of the Garage along the side of my house. I am figuring at this point the Sewer is approx 5 Feet below Ground Level. How much of an incline does the Sewer have to have to be able to keep things running smoothly? in other words whats the rise/run calulation to figure out if I can run a 20 foot sewer pipe and still keep it below the frost line.

Second Question (related) :roll: Does anyone know what the Frost line is in Southern Ontario? Some people have told me 3 feet, others have told me 4. At three feet I think this run of Sewer is doable at 4 Feet I don't think I will be able to do it unless sewer pipe only will require a drop of 1 inch or less per foot of run. any additional resouces you can point me to would be much appriciated.

[Rich]

Depending on what diameter your pipe is (typically 4" for drain and waste) will dictate the min/max slope you can have. 3-4" should have around 1/4" per foot slope. Anything above 3/8" or 1/2" per foot and you run the chance of leaving some solids behind (not good).
I would imagine your frostline is somewhere around 4'. In MT it's 38" and it does get a bit colder in Ontario.

[mjpliv]

If what I have heard about the building codes in Ontario is true, you will have some difficulty getting permits to do all of this.

Have you looked into the rules regarding having two occupancies on a single serviced lot? Was the slab under the garage designed by an engineer as a monolithic slab c/w grade beams? The garage exceeds the allowable maximum of 600 square feet for a simple slab on grade.

[macgyver007]

I am not sure what you mean by c/w grade beams?
I was not the one who origionally constructed the garage so How would I find out after the fact.

Thanks for the help
Jason

[mjpliv]

A grade beam refers a section through the slab designed with upper and lower/ inner and outer rebar restrained with rebar ties that will allows the concrete slab to support itself and the loads it carries in the event that a portion of the bearing soil no longer exists due to settlement or erosion.

The National Building Code Of Canada (1995) has no provisions for structural concrete pads in Part Nine. It only covers those concrete slabs that carry no loads (Section 9.16.0.0). For any Floors-On-Ground (slabs) that support loads from a superstructure, the NBCC refers you to Part Four which is the domain of architects and engineers.

[macgyver007]

about the slab question, There is rebar runnig through the slab, it is build with a footing reaching approx 4 ft underground all the way around.

From all of the postings I have seen I am able to figure out that for a 4inch ABS which is what I am using I would require approx a 2% slope. In this posting I have seen .25 inch drop per foot. Am I correct in looking at this and saying that in a 50 foot run I would need 12.5 inches of drop? Could I use a lesser drop say of 1%? meaning about 7 inches in a 50 foot run?

Comments welcome.

[mjpliv]

I have a completed Home on a Single Building Lot. From the Back of the house I have about 10 Feet of Green Space and then there is a 30X30 Cinder Block 2 Story Garage. (Also Mine)
The House measures approx 22 X 70 Single Story with a Full Basement.
The Garage is Completely Above ground with a Poured Concrete Floor.
The Garage is furniched with a Forced Air Natural Gas Furnace completely seperate from the house.


I am sorry, when you said the garage was "all above ground" I assumed it was a slab poured on grade.

Are you saying that the garage has a complete 4 foot frost wall/footings with a concrete floor poured between the foundation walls? If that is the case then we have a whole different kettle of fish. As long as you can get a permit to build it then an engineer should not be required.

[macgyver007]

HI thanks for the reply, Yes thats exactly what I have. Its a 24 X 24 2 Story Garage detached form the house. I have been digging in the yard and I at about 4 foot 6 inches Down and belive I have hit the bottom of the footing wall. The entire inside of the garage floor Looks like it was poured seperatly from the footing, But there is rebar built into it because I wrecked a concrete Drill bit trying to drill a test hole. There is approx 6 inch Concrete Floor throughout the garage. This garage was built to start a plumbing business and no expense was spared while constructing it. I personally have never seen anthing constructed like this before on a residential lot. Pretty sure you could use it for a bomb shelter. :-)

[mjpliv]

Keep in mind that your second floor structure will have to be entirely supported on the exterior walls of the garage so you are looking at an clear span, engineered floor system and roof trusses or an engineered attic frame truss system. There should not be any cost to you for engineering if you have them designed by the product supplier.

The last time I clear spanned 30 feet the the joists were 16" thick (OJ2000 joist system) Your roof truss manufacture can also manufacture plated, open web floor joists.

[macgyver007]

IF I was to explain it this way, THere is a Steel I beam that runs N/S in the garage in the middle, Traveling E/W from that to the walls there are True 3 inch by 12 Inch Floor Joists. On top of that there is 3/4 inch by 6 inch T&G flooring. I have covered that again in 1/2 inch OSB. THere is 0 flex in the floor now and all is supported by the exterior walls. The I beam is aprox 8 inches wide by 18 inches High.
The roof system again has another series of e/w Beams connected to a central Wooden Beam. The beam is supported in the middle by a Supporting post and is mounted directly over the I beam under the floor.

I think its going to be heavy enough to support what I am looking for.

Do you have any comments if I can use a 1% grade instead of a 2%?

[mjpliv]

I went back and re-read your original post. I missed the fact that it was a two storey garage. Sorry about that!

As long as the building inspectors are happy with the place being used as a dwelling then you should have no problems. You will have some code issues to deal with like access (stairs, egress windows, etc) and sealing the living space away from the garage space (sealed doors, automatic closures, etc)

[macgyver007]

Thanks again for the replys
J

[snkandersen]

3" and ynder 1/4 inch per foot and 4" 1/8 of an inch per foot, either way you have lots of room to get your proper fall and when you tie in just 45 into the tee or double 45 this is comingh from a plumber not a jack of all.
peace

[snkandersen]

LOL I'm about 6 years late

[homebild]

Better late than never! :)