Some advice needed in building a car port.

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kleinbiker1

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I have recently purchased my first home. Up until now I've been a renter. Garage space has always been important to me as I tinker with cars a lot. Even when renting garage space has been important. Now that I've bought I decided to let lot size and location trump garage space as I know I can build more down the road.

In this move I have gone from a 2.5 car garage to a 1.5 car garage and I'm feeling cramped already. I don't have the finances to build a whole garage right now so I'd like to build a simple car port off the side of the current garage for now.

I have a plan in my head but have a few questions that I was hoping could be answered here. First lets start with header attachment onto the cinder block garage.

1) Should I use pressure treated lumber?
2) Should I use threaded rod all the way through the cinder block (I read this somewhere) or should I use some type of masonry anchor?
3) When choosing the header height I have a few things to consider. Should I attached the joists with hangers or toe nail them on top of the header? Also there is a small 1/2x8 facia trim. Should I set the header below that or should I remove it.

4) This somewhat relates to #3....should I attempt to integrate the new roof with the original roof of the garage?

Hopefully these aren't too many questions to start and there are a few out there with experience in this area.

Thanks in advance and below are a few pictures of the side of the garage I'd like to put the carport.

I only plan to have it go up to the fence right now, and yes I realize I'll be driving through the yard. Initially I just want a car I don't use often to at least be out of the weather for the winter.

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Your going to need a permit to do this and your small lot size may or may not allow you to even build one there. I'd check that out before even filling out the paper work for the permit. The zoning dept. is where I'd start.
The reason a lot of DIY addition like this have roof problums is they tryed to build it the way you suggested.
The fashis and soffit will need to come off, the old roof needs to be cut back to allow the rim joist and any rafters (which your going to need later on to install a ceiling) the rim joist and rafters need to be sitting on top of the block wall not just attached to it. The new roof needs to be sitting as far up on top of the old roof as possible, the peak would be the best place. The reasons being your going to need all the height you can get so the rafters need to be at least as high as the ones in the old garage, without enough slope the shingles will leak, build up with snow, and the roof may sag.
The future slab is going to have to be pored high enough so water will not get in under the bottom plates or you sheathing and siding is not to close to the ground. By raising the slab heigth the head room is reduced.
I'd only use pressure treated 6 X 6's not 4 X 4's, 6 X 6's will have less twist, can have the sides cut into so the rim joist can not only be attached to the side with through bolts but be sitting on the notches, I'd counter bore for the heads of the carrage bolts so in the future you would have a flat surface to attach the sheathing to.
I'd cut the rafters so there was at least a 8" (12" would be better) over hang so when water comes off the roof there's less splash back.
 
I appreaciate the thorough reply. I will certainly check the zoning laws around here, but I highly doubt that my lot size will be an issue. I'm on a double lot and I already have 3 times the avail yard as most homes in my neighborhood. While I currently only have a 1.5 car garage there are some properties in my neighborhood with a 3 car garage on a single lot.

I'll look into the other ideas/problems you suggested. The rental home I moved from was 6 miles from here and had pretty much the same carport idea and didn't have a single issue in the few years that I had lived there and I was told the carport had been there for about 10 year. The roof on that one was virtually flat as well. It was a pretty simple design with some gravel under it. I certainly had no intentions on making the roof close to flat and hoping to make it as steep as possible while still leaving at least a little head room at the far edge. Also the free standing edge was held up with 4x4's and didn't have any indication of twisting.

While you certainly raise some good points, I'm thinking perhaps your idea could be a little overkill. I've benn known to be wrong so I'd certainly like to hear some input from other as well.

Thanks,

Chris
 
Lot size may not be the issue, but you could get shot down on setbacks. If your carport is too close to the property line, the zoning board - or your neighbor - may object.

I don't know how long you were in the rental, but I think a flat roof is just an invitation to trouble, or least increased maintenance. Remember, it's YOUR house now, and you will have to take care of it, and protect the value of your investment. My next-door neighbor has a flat-roof carport, and although it has been standing for at least thirty years (maybe a lot longer) it is now ready to fall. The roof has been leaking for years. The corners are all rotted and there is a visible sag (visible for years now). Make sure you account for snow load in your plans.
Also, do you have a plan to keep the gravel from spreading out into your yard?
Just a thought; have you looked at those tent structures that you can get at Cabela's or someplace similar?
 
It could get shot down on setbacks even if the car port comes no closer to the property line than the existing garage? Remember that I was only going to take the carport to the existing fence in the pictures. What can't exactly be seen in the picutres is that the direction the car port would be coming off the garage is the direction of my second lot.

Anyway, like I said above I would never consider a flat roof. I'd like to get the roof as steeply pitched as possible and still be able to walk under the low end, even if it's just barely.

In regards to being a homeowner I agree with you 100%. If this were a rental property I'd have already started to throw something up. I would like this to be a fairly decent job. I also would like to get something up before winter totally sets in so I was looking for something simple to start with. 2x6's are fairly cheap and if I needed to take it down and do it over somewhat I'm okay with that. I was initially thinking about using that corrugated roofing material and then upgrade to real shingles down the road when I learn how to do that. In regard to the gravel my plan was to create an edging with 2x4's to keep it in. I only plan to have gravel there for a season or two until I can put a slab.

In regards to those tent structures, I think those would look a whole lot worse than anything I could build myself, not to mention I can imagine those have any sort of snowload rating.
 
I'm a builder and remodler not a weekend DIY, the way I suggested building it will be at least double the strength, will get rid of side sway will allow you to have a building that will never have to be worked on from being to weak to hold the snow loads.
Plus the best part is the better materals would only cost about $50.00 more.
I get to see DIY shed style roofs all the time, mostly when I'm there to rip it all down because it was built wrong in the first place.
It a matter of pay now or do it again later and have to pay again.
 
That would be fine except then you would have two roof lines acting as a funnel dumping rain and snow at the foot of the garages foundation.
 
I'm a builder and remodler not a weekend DIY, the way I suggested building it will be at least double the strength, will get rid of side sway will allow you to have a building that will never have to be worked on from being to weak to hold the snow loads.
Plus the best part is the better materals would only cost about $50.00 more.
I get to see DIY shed style roofs all the time, mostly when I'm there to rip it all down because it was built wrong in the first place.
It a matter of pay now or do it again later and have to pay again.

I didn't think you were a weekend DIY...that would be me. I understand that all your suggestions are really to increase the strength but following your advice quickly turns this project into something I can't handle right now. Attachng and sealing a 2x6 to the cinder block, digging deep holes and cementing in a few 4x4's (or 6x6's), running some rafters and teaching myself how to lay roofing paper and shilngle are all well within my current scope but......cutting into the original roof and attaching to those rafters quickly puts it beyond me, at least until spring. Something in the middle where I sink the 6x6's as recommended but only attach rafters to a 2x6 attached the cinder block and then use corrugated is what I was maybe thinking. Not sure on the price of corrugated but the 2x6 price is low enough that I"m okay pulling those off in the spring and getting longer ones and attaching into original roof in the spring.

What are thoughts on additional support posts against the garage wall for support AND attaching to the cinder block for increased stability?
 
That would be fine except then you would have two roof lines acting as a funnel dumping rain and snow at the foot of the garages foundation.


Yeah I totally agree on this one, plus these kits likely triple the cost of what I'm looking to do and look horrible in my opinion.
 
This is basically the idea I had but making the outer end a little lower to increase the pitch of the new roof to help handle possible snow loads.

Extreme How To
 
If it were mine, I'd be tempted to use 6 x 6 treated (incised) posts, set in concrete, below the frost line--both for their additional stability, and their ability to be notched and through-bolted at the header connections (as joecaption suggested), making a far more rigid and stable structure. And I don't think I would ever rely on concrete block, or especially the lighter cinder block, to attach a ledger to. One heavy snow event, and it's all over, with the entire wall pulling out and collapsing. Much better to make the carport free-standing, with 6 x 6s adjacent to the block wall to support a "high-side" header at any elevation you want. Could even cantilever the joists/rafters over it, taper-cutting the ends to enable the roof sheathing to butt up to the garage roof, with flashing tucked under the garage shingle-line you intersect.

Something else to think about--if you're using 2 x 6s for joists/rafters, put them in at 12" centers. Much less deflection under any load than 24", with better performance. I don't think you mentioned a span length, but 2 x 6s at 24" centers are pretty much maxed out at a span of just over 7', using an allowable bending stress of 1500 psi, allowable deflection of L/240, and a 50 psf live (snow) load.

Thinking outside of the box, why not consider building a complete roof now, tied into the existing garage full-height, coming off as a "T"-eed gable? That way, you wouldn't be tearing things out and re-doing them in a year or two, but simply infilling the walls and floor to make a "real" garage addition when you can afford it.
 
By attaching a ledger the way you suggest you will loose about 16" of needed heigth. Not sure why it's behond your abilitys, it may be something you have not done before but it's simple to do, just remove a few cources of shingles, mark a line with a chauk line and cut the roof sheathing just enough back to fit the 2 X 6 rafters for a ceiling. Then just nail the two together sitting side by side.
But the outside post and beam needs to be in place before anything else gets done. If you do it with the 6 X 6's I suggested, use 1/2 carrage bolts through bolted and use 2 X 10's on both sides of the 6 X 6's, you could span the whole distance with no center post.
No having to find a hammer drill with a long enough 1/2 bit to go through the block, no drilling, no having to attach all those joist hangers, no having to buy all those long carrage bolts washers and nuts.
PS make sure you call Miss Utility or whatever it's called in you area before any digging.
 
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