[kris77]

Posted this over on contractor talk and decided to post over here as this is my own personal project instead of a project from my business. I might get yelled at over there for posting a DIY project....

I'll try to be as detailed as possible and hopefully somebody can chime in and explain this to me.

I'm planning on pouring a 16x20 patio/porch. Maybe a 16x24. Havent decided exactly yet the length. It will be attached to the back of my house on the long side. My back door is sitting about 13" off the ground right now. 16' out it is about 8" high with the back door. The yard/hill gradually runs downhill toward the house. About a 4-5" slope within the 16'.

1st question.

I would like the patio to be even with the door and have a walk out porch/patio instead of stepping down one step.

I'm assuming I will need to dig down and pour a footer around the perimeter and then lay a course or 2 of block to get it up to where its even with my door correct? I was told to dig all the way down to the footer of my house and pour my footer for my porch/patio level with that footer and lay the same 4 courses of block my foundation has. Is this necessary?

2nd question.

Eventually, this will have 6x6's sitting on it with roof trusses over head and a nice gable roof over it. WAY, WAY down the road. But I need to plan for it now when building it. Is there anything I need to do to support the roof? Do something different in the corners?

3rd question.

Up against the house, I worry about the slab settling and falling. Will I need the footer down the entire length of the house as well? Can i tie into my existing block somehow to support the weight? Any other options?

Thanks for all the help in advance.

 

[ron45]

Monolithic..?

 

[concretemasonry]

kris -

You left out some important information - like where are you climate wise? Also, a photo will save everyone some time to give you a decent answer. There is a thing like "frost"/heaving and some localized soil problems.

Being "even" with the floor is not a good idea.

Do you really want to attach the patio slab to the house foundation?

Do you want the post s bearing on the patio slab?te from the slab?

Do you have building code to protect you?

Dick

 

[Daniel Holzman]

I agree with concretemasonry. You really do not want the patio level with the house threshold, too easy for water to get in to the house. As for the slab, it will not settle if you prepare the subgrade correctly. You need the footers to support the structure, the slab is just there to walk on, and has no structural importance. There is no reason to connect the slab to the house foundation, proper subgrade preparation will support the slab, and the footers should be designed in accordance with local code requirements, as dictated by local soil conditions and required frost depth.

As for supporting the roof, you seem to be planning to use 6x6 posts, which should be fine. Each post will need a footer, design dictated by soil conditions and local code requirements. Local code may require (and it is a good idea anyway) that you use galvanized standoff brackets such as the type Simpson makes to support the posts above grade.

 

[ron45]

Okay, why can't the slab be just below the threshold.?

 

[kris77]

Ok, sorry.

Im in WV. 2' down will get me below frost line here. Which i knew already. My main question was if I needed to go all they down the 4 or 5 courses to my footer of my house, or if i could just go down the 2' and be good.

I dont want to tie into the house if I don't have to. I know the house and patio will move differently so if they can be separate, that is great. I just dont want the patio to start sagging in the middle next to the house. I've seen lots of those type of jobs and i want to prevent this. And When I say even, I actually meant just below the threshold. I'm not a complete idiot when it comes to this....lol I know I need some kind of lip there to prevent water from entering the house. I just would rather not have a 7" step down if I can help it.

Basically my question was if I needed to go all the way down to my current footer and start from there....and if i needed a footer along side the house so it didnt settle next to the house....

Hope that makes sense. And thanks for all the replies. I'll try and get a pic tonight.

Basically I want to know if i can do this....Minus the lip for brick.

Or if I need to go to the footers of the house and lay blocks first.

Thanks

 

[jomama45]

If the roof will be attached to the house later, the porch should have hte same type of foundation as the house, meaning you you should verify that you only need 24" of frost protection, and then plan on laying at least 3 courses of block on top of an 8" thick concrete footing.

I would install some block piers (typically 4" x 16" block layed on the existing footing) every 5-6' along the house as well, and would not rely on dowels into hollow block to support the porch against the house.

Last, if you get snow in your area, and you plan to have a storm door on, keep in mind you may not be able to open it a few times in winter w/o at least a 4" drop down to the porch.......