Extreme Garage Makeover

[GirlNeedsGarage]

Hello, I'm brand new here. Go easy on me.

I have a historic 103-year-old house that I am restoring. Unfortunately, I have a POS garage from the 1990s to go with it. The garage wasn't even built to code, as far as I can tell (no man door for starters which I know is code here). I'm near Cleveland, OH btw.

My current garage is 20x20 on a slab with a gable roof. The slab has a little concrete wall going all the way around, about 3.25-3.5" tall that the framed walls sit on. It is framed on 24" centers (problem #1). The garage door opening is 15' 10" wide by 6' 5" tall (with (2) 2x12" for a header). The framed wall is 7' 3" tall, the total height, to the floor is about 7' 7.5".

This structure is holding up just fine but the roof has totally deteriorated and there are holes in it now, including a big one where a branch landed on it. The siding is made out of some kind of particle board that just absorbs moisture, swells up, and falls apart.

A few years back, I disassembled an old carriage house and brought all the parts home. Carriage doors, ship lap siding, 2x4s, etc. I originally planned on building an entirely new garage, using these parts. Now, I just want to keep my existing foundation/footprint and make mine waterproof again and prettier. I intend to use the ship lap siding and carriage doors in the makeover as well as brand new slate I have leftover from doing a new roof on my house 3 years ago.

This presents several problems. #1, I assume 24" centers are not good enough to hold up slate? I originally figured I'd remedy this by just adding a new stud between the existing studs, making it 12" oc. I know that'd be overkill but it seemed like the easiest way. Then, I wanted to tear down the entire roof structure and build a steeper pitched roof (mine is probably 4/12) to allow for some attic storage. I also want exposed rafter tails on the overhangs (maybe 12"). Currently, there are no overhangs.

I also took the old side door and a window out of the carriage house, to add to my doorless, windowless garage. Basically, I want the garage to look like it belongs here.

Here is problem #2. These big, beautiful carriage doors (there are 4 of them) are about 50" wide x 8' tall. Making them taller than my existing walls, let alone the door opening. 15" taller, to be exact. Obviously, I'm not cutting that off the doors.

At this point, unless anyone has any better suggestions, I think the only way is to just start over. Build new walls 8 or 9 ft tall, 16" oc. I was trying to avoid that but I'm not seeing another way to open the door opening tall enough for these carriage doors.

Now, my question is, what is code for the header for a 16' opening? This header will be supporting the weight of these 4 giant, heavy carriage doors, plus the slate roof. The current header is (2) 2x12 and it is over 15' wide. Will I be able to reuse that? Or do I need to add another 2x12 and make the front wall out of 2x6s? And if I have to build it out of 2x6s, is it ok to just build that wall out of 2x6 or do I have to do the other walls as well?

Any help is appreciated. I'm at the very beginning planning stages right now. Hoping to start the project in a couple months.

 

[Resu]

Do you have any pictures you might be able to add? May prove helpful for the guys / gals on the forum for reference. Sounds like a great project!

 

[GirlNeedsGarage]

I am trying to add pics that I have stored in google photos but they just keep coming up as broken links. I have share settings formatted correctly on the google albums so I don't know what the problem is.

I did just read IRC codes (http://codes.iccsafe.org/app/book/content/2015-I-Codes/2015%20IRC%20HTML/Chapter%206.html) on header spans and for wood, nothing comes up with a span of 16'. And the number of jack studs required for a 16' span is 6 on each end, which I don't have room for. I'm thinking I'm going to have to have a separation with a support in the middle?

 

[rburke65]

First of all welcome to the Garage Journal. Carriage doors...are they not hinged on the sides? Sounds like it might be time to start over. May be more cost effective.

 

[KDXSR5]

So, you want to replace the roof structure, reside it, and basically reframe it? I would tear the POS down salvaging what you can (sounds like just the 2x framing from your description) and rebuild on the same footprint if you are happy with the size. This will give you the structure you really want without the headaches associated with the current POS described.

 

[chaosracing]

Hello, I'm brand new here. Go easy on me.

I have a historic 103-year-old house that I am restoring. Unfortunately, I have a POS garage from the 1990s to go with it. The garage wasn't even built to code, as far as I can tell (no man door for starters which I know is code here). I'm near Cleveland, OH btw.

My current garage is 20x20 on a slab with a gable roof. The slab has a little concrete wall going all the way around, about 3.25-3.5" tall that the framed walls sit on. It is framed on 24" centers (problem #1). The garage door opening is 15' 10" wide by 6' 5" tall (with (2) 2x12" for a header). The framed wall is 7' 3" tall, the total height, to the floor is about 7' 7.5".

This structure is holding up just fine but the roof has totally deteriorated and there are holes in it now, including a big one where a branch landed on it. The siding is made out of some kind of particle board that just absorbs moisture, swells up, and falls apart.

A few years back, I disassembled an old carriage house and brought all the parts home. Carriage doors, ship lap siding, 2x4s, etc. I originally planned on building an entirely new garage, using these parts. Now, I just want to keep my existing foundation/footprint and make mine waterproof again and prettier. I intend to use the ship lap siding and carriage doors in the makeover as well as brand new slate I have leftover from doing a new roof on my house 3 years ago.

This presents several problems. #1, I assume 24" centers are not good enough to hold up slate? Even if the framing was 16"OC, the roof framing was not designed to hold slate, unless that is what was originally on it. If you really want slate, you are going to have to use rubber slate and that still had weight issues with your structure.I originally figured I'd remedy this by just adding a new stud between the existing studs, making it 12" oc. I know that'd be overkill but it seemed like the easiest way. Then, I wanted to tear down the entire roof structure and build a steeper pitched roof (mine is probably 4/12) to allow for some attic storage. I also want exposed rafter tails on the overhangs (maybe 12"). Currently, there are no overhangs.
At this point, you might be better off tearing everything down and restart. Get engineered trusses. If you can, I would reuse the lumber.

I also took the old side door and a window out of the carriage house, to add to my doorless, windowless garage. Basically, I want the garage to look like it belongs here.

Here is problem #2. These big, beautiful carriage doors (there are 4 of them) are about 50" wide x 8' tall. Making them taller than my existing walls, let alone the door opening. 15" taller, to be exact. Obviously, I'm not cutting that off the doors.

At this point, unless anyone has any better suggestions, I think the only way is to just start over. Build new walls 8 or 9 ft tall, 16" oc. I was trying to avoid that but I'm not seeing another way to open the door opening tall enough for these carriage doors.

Now, my question is, what is code for the header for a 16' opening? This header will be supporting the weight of these 4 giant, heavy carriage doors, plus the slate roof. The current header is (2) 2x12 and it is over 15' wide. Will I be able to reuse that? Or do I need to add another 2x12 and make the front wall out of 2x6s? And if I have to build it out of 2x6s, is it ok to just build that wall out of 2x6 or do I have to do the other walls as well?You really need to have one engineered, that size will need an LVL (Laminated Veneer Lumber, steel or a LVL/Steel hybrid (called a flitch beam) made up. Most truss places can help with that to.

Any help is appreciated. I'm at the very beginning planning stages right now. Hoping to start the project in a couple months.

Hope those help

 

[GirlNeedsGarage]

Like I said, I was planning on completely restructuring the roof anyway, with a steeper pitch to allow for an attic storage space. So there was no issue with the slate. I already have 4 pallets of real Vermont slate ready to go. The issue is just with the walls being too short and being on 24" centers. So I've basically decided to rebuild taller walls. I doubt I can use much of the existing studs in the rebuild for anything, since they are too short.

I think I've just decided to break the large garage opening into 2 smaller openings and have each carriage door swing outward. That will alleviate the issue with the header. And also another issue I was having trying to figure out how to use these carriage doors since the original hardware had them opening inward, accordion style, which wouldn't work if a car was in the garage.

Thanks for the feedback. I'm sure I'll have more questions as I continue planning.

 

[ssdave]

I'd just tear it down and start over. If you don't, all you're saving is the wall studs, and they're too short. As recommended above, get the beam sized for the garage header by someone that considers all the loads. One or two LVL's will be what you need, and the depth can vary depending on what loads are on it. I would also have the shear paneling for the wall that has the garage door detailed out; using shear nailing, holddowns and careful placement of the OSB sheathing on this wall will determine it's stability. There's great narrow wall details out there that meet code and give adequate bracing.

Going with attic trusses for overhead storage is a very economical way to get low cost, reasonable quality storage space.

Good luck with your project!

 

[GirlNeedsGarage]

Yeah I've come to the same conclusion at this point, just start over. Even if the walls were tall enough, the fact that I would have to make them 12" oc would mean buying those studs for in between plus enough roofing rafters for 12" oc rather than 16". I think it'd end up being more expensive than just starting over with 16" oc.

I looked into the trusses and the ones that are built for attic space are really expensive! I think it'd be cheaper to just build a ridge board design myself. I'm gonna talk to the inspector about everything first and get his opinion.

As for the doors, I decided last night to just do two separate doorways (single car doorways). So each carriage door would open outward and there'd be a little wall between doorways.

 

[chaosracing]

You will be surprised at what they will make you do to make your own roof support system. Especially since you are using slate. You need to go with thicker roof deck (suggested is at least 3/4" OSB even with trusses) just to support the slate so it doesnt bow between rafters. Not sure how thick your slate is, but if its standard 3/8" thick and a 7/8" roof deck, you are looking at 16lbs per square foot. Then calculate in the snow load for your area. I looked it up and its 20lb to 25lb per square foot for your area.
I am not saying that building your own roof system is not possible, but you will more than likely have to use all engineered systems anyway (LVL's and engineered I joists) so in the long run the trusses will be easier and probably more cost effective.

 

[chaosracing]

Just so anyone going thru this post doesnt have to search for it, please put your location in your profile, thanks.

 

[GirlNeedsGarage]

Thanks. I added my location.

I rebuilt the roof structure of my porch (10x25 gable) before having the slate installed a few years ago. Replaced some rafters and re-decked the entire thing. I used 1x8 boards, like they originally used 100 yrs ago, with a small expansion joint between. Grace ice & water shield over the entire thing, and a ridge vent (will be adding soffit vents for air intake). I don't like the idea of osb or plywood under slate. I'll ask the inspector about it. I just sent him an email with some other questions about the roof rafters and headers.

Interestingly, the original carriage house that I took these parts from, (about 110 yrs old probably), had 2x4 roof rafters that had originally held slate. They were pretty bowed though.

 

[chaosracing]

I did a slate install about 15 years ago. The contractor used 3/4" OSB. We used grace ice and water shield on entire deck, then red rosin paper. We were using a mix of 3/8" and 1/2" thick vermont slate. I just went past that the other day and roof still looks as goods as the day we finished it. Just curious, but why don't you like OSB or plywood under slate? Thats all you see now. Even on reroof, most will skin over the 1x8 with minimum 3/8" OSB to cover all gaps and cracks.

Since you will be starting from scratch, you will not be grandfathered in so you will have to follow all new and current building codes. Meaning what they did 100 years ago is not what will be accepted today. I am in no way saying that old construction is bad (in many ways its superior to todays) but you have to go by building codes.

 

[GirlNeedsGarage]

I have a huge slate book and I believe I read not to use plywood or osb under slate. I know a lot of preservationists/contractors who only work on old houses and I doubt any of them would use either of those products for a slate roof. My house is 103 years old and when we did the roof tear off, there were only about 3 boards (1x8) that needed to be replaced on the entire roof. The rest of the decking was still fine.

15 years is hardly a test of time when using a product (slate) that will last hundreds. I don't see osb holding up to the test of time. That's just my opinion. I prefer to spend the extra money on solid wood and have it last forever.

I just looked on Joseph Jenkins website (he is widely considered to be the slate God and most well known slate contractor in the US, literally wrote the book on slate). This is what it says:

8. Poor sheathing materials: The roof decking must last as long as the slate. A good roof deck should last the life of two slate roofs, or about 200 to 300 years. In any case, a roof decking material under slate must have a known longevity of at least 150 years. Materials that have been tried and proven for this purpose include lumber boards and battens from 3/4 inch to 1.5 inch thick rough-sawn, planed or tongue-in-grooved, from a variety of species of wood. Plywood, laminated woods, particle boards, and materials that rely on glue for structural integrity are sub-standard roof decking materials for slate roofs and should be avoided. Yes, you can install slate on laminated or glued decking materials, but a compromise on longevity is likely to be the result. If a slate roof is to be built to last, the roof deck should be solid boards, not glued sheets of wood.

http://www.traditionalroofing.com/TR4_mistakes.html

I'm pretty anti-new-construction, for the reasons illustrated in my own POS garage from the 90s. The roof is collapsing, the siding is disintegrating, the studs are too far apart. New construction is not made to last. It's made to be quick and cheap.

 

[-Brent-]

I feel like all the 24" OC garages I've seen over the years all came from shed building companies. Not that it's horrible but really, that's pretty much what you have, an oversized shed.

With the work it needs and what you'd like to accomplish I'd look into a tear-down and getting one of the Amish builders out there to build what you want.

 

[Moose97]

Someone said earlier that the 16' garage opening would require an engineered beam. That is correct. As we are in the age of fast-growth lumber, engineered lumber is many times the better choice.

 

[chaosracing]

As we are in the age of fast-growth lumber, engineered lumber is many times the better choice.

And that is precisely why the usage of OSB, LVL's and other engineered products. Trust me, in 100 years, as long as the slate roof I did maintains water integrity (which it should) the OSB will be there as strong as ever. The newer stuff is tested to extremes (I took those courses in college) that we will not see. Unless you plan on buying old growth lumber, your 1x8's you pick up today are not the same 1x8's that were used 100 years ago. Believe me, I would love to use old lumber as well because the new lumber is junk, but thats where we are.

BTW, we talked to Vermont slate before installing the slate, they had no issues with the OSB at all. National Roofing Association has no problems either.

 

[ssdave]

The use of boards and gapping (skip sheathing) is the reason those roofs can last. The system is self venting. Air moves through the gap between the boards, and out the shingles. It carries moisture with it, keeping the wood dry and rot free. It also substantially cools the roof.

If you put tarpaper or ice and water shield over the boards, they often rot quickly. You have to then make sure you put in soffit and ridge venting, and treat the roof just as if you had put on asphalt shingles.

So, if you really want to skip the OSB and go with boards, either lay them the traditional way and retain the venting properties, or treat the boards like you had used OSB and vent it the same way as OSB.

The heat buildup from not having microventing all over the roof surface may damage the boards also, and your ice and water shielding.

 

[matt_i]

I personally believe if the roof is maintained, be that metal, asphalt, or slate, todays buildings are pretty much 100 year structures (few other caveats but trying to keep the essence brief!). I wouldn't worry about the OSB...that's literally going to be someone else's problem

Tangential, but to illustrate: my Dad bought some old-growth oak spindles he bought from an ancient carpenter who said he took them out of a house built around 1900. My Dad's opinion of the oak is that it was probably 100yo at the time the tree was harvested (guesses & hearsay possible, but accurate to the best knowledge). He used them on the wood lathe to make into tool handles. The wood lasts a lot longer out of the forest, kept dry and under roof, than it does au naturel in the forest. If the glues start to significantly decay in ply and osb humanity, is going to face a serious crisis someday.....

 

[Zeke]

I have to agree that by the time you remove the old roof structure and the existing siding that's time to build new walls. Bear in mind that old lumber is not allowed in a new structure, only if you were "remodeling" whereas you could add new lumber in the walls to improve the existing.

Tear it down to the foundation and do it right. There are many ways to add some character to your new/old garage when reconstructing. Like maybe a bump out of a cantilevered gable over your carriage doors.

You can thank me for adding expense to your project later.