Need Help beefing up Garage structure
Hello,
My garage/car port is 12′ high up to the rafters. 32′ wide, and 26′ deep. As the picture shows the two front posts are only 4x6s, and inside the studs are 24″ oc and not 16″. The trusses are also just 2x4s – I’m not a builder but the structure looks very thin to me. However it is 21 years old and still standing with no structoral defects, so what do I know…..
I want to inclose the front, and create storage inside. I think the original builders had RV storage in mind. And I’m on a tight budget.
So I’d like to know how this structure should be beefed up inorder to reach my goals of adding double-car door (16’x7′), inclosing the front and adding a small loft plus storage-racks. Thereby making it a nice usable space.
I can take more pictures, however the garage is now covered wall to wall with un-organized stuff since our move in. It is no better than a car port with the interrior exposed to winter humity of 100%.
Your expertise is appreciated.
Replies
Seems to me that one problem you have is that there's not much to keep it from racking.
An X brace on the ceiling would go a long way toward making it more rigid.
What I see there looks pretty normal to me. No reason to worry about any of it.
read the post
...rather than just look at the pretty pictures.
If the OP's goal is to put a pair of 16' wide garage doors on the front of this structure (as indicated), then I'd say there is reason to worry about it. The front posts are only about 10.6' feet O.C. Whoops!
In order to meet the goal, the OP is going to have to reconfigure the existing front posts and re-engineer the resolution of the roof loads at the front wall of the structure. IMO, it's time to consult with a P.E. for this project. Also, I believe it is going to be difficult to fit two standard 16' wide doors (with space for track hardware) in available length of structure. YOu might have to go custom width for the doors or re-think another combination of standard doors. I recommend consulting with your garage door supplier/installer before working with the P.E.
Read the words: he said "door."
Doesn't matter.
I read the post. It was vague as to door intentions. However, it is a non issue because it didn't matter If it was a pair of double car garage doors...or a single double car door. Either door configuration scenario requires a min. 16'+ clear opening. With three apparently equidistant posts (or close to it), the largest clear opening on this existing garage has to be less than 10'-6".
It is a point that there is no header over the existing openings. Might be OK in some parts of the country, but not really trustworthy with an 18" snow load.
Here we go again...
Dan,
You don't know that there aren't header(s) installed in the front wall. There most likely is. It's required in all parts of the country because all parts of the country are susceptible to the laws of physics; including gravity. To the question of whether existing conditions are adequate? 21 years of resisting gravity (certainly without visible signs of imminent collapse) says it is. Whether it meets current code or the requirements of future modifications is unknowable (at least to this forum at this point). That's why I recommend the advice of a P.E. --not someone like you.
James,
I would build 2 8' walls and put the 16' garage door in the middle with a glulam header. Put a 3-0 6-8 door in one wall and a window in the other. No big deal and no need for one of those injunears.
KK
It's all relative
Remember, you're gonna need some additonal continous footings under them thar 8' walls. Sure, you can do that prescriptively as well. However, as soon as you use a gluelam, you've enlisted the need for an engineer. You're paying for their service in the price of the material. That's why they call it "injuneared" lumber.
BTW, It's only "no big deal" if you aren't the one digging the footings and pouring the concrete.
James, the spacing of the studs should not worry you at all. The 2x4 trusses are also ok. If they were rafters, then you would be getting different advice.
Assuming that you dont need to address the front "entrance section" of the slab, you have 12' H to work with so you should not have any problems.
Frame the front up, a new header for the garage door, below whatever is already there to transfer loads adequately and close it in.
Not sure what you mean by a small loft but anything like this would need to be below the trusses. Do not cut any of the cords on those trusses.
Good luck.
mark122 wrote:
Assuming that you dont need to address the front "entrance section" of the slab....
Good luck.
Why would you assume that? New header for 16' wide door should have adequate footings for roof load. Existing concrete slab should be verified for load capacity at new bearing positions. if it's a typical 4" slab on grade, then that's not gonna cut it.
Why would you assume it is a 4'' slab on grade?
The slab and building have been standing for (if i remeber correctly 20+yrs) without structural issues. This says to me that more than likely this slab has proper footings, so based on what that says to me i say "assuming you dont need to address the front of the slab", then this would be my approach.
There are currently 2 post bearing on the slab, i would be fine moving one of those over and tacking on a little bit more weight, the remaining of the current opening would be taken care of by a wall.
Mark,
Even if it was a 4" slab I wouldn't hesitate to build the two side walls and put in a glulam. Sheathed right the load would be spread enough for this little light roof.
KK
four seasons
You're right. That is a light little roof. Dead load design requirments are probably only 10# per sq.ft. Your forgetting about one season where snow loads (depending on where this is) can be many times that.
I didn't assume it was. I begin that statement with the qualifier "If".
BTW, the existing posts could be bearing on additonal point load footings poured before (or with) the slab. Those do not necessarily translate as adequate for new rought opening post locations. Key words I have used here are "could" and "necessarily". I' m not assuming anything here (and never have) , because the OP has given very little specific information. I only responding to the information that was given and not letting my imagination run wild with unsubstantiated structural solutions.
But you are assuming alot. In this case you are assuming the worst that the slab is not capable of supporting a point load change, hence the critical comments to any suggestion made under the assumption the the slab is adequate for changes.
First off, just like you prefenced your comments with "could" and "necessarily", I prefence my comments with "assuming".
You assumed the worst case scenario, I assumed a better case scenario, and based on those assumptions we are all making a recommendation.
Do you really think that it is more likely that someone took the time to dig two load footings vs making the front of the slab a proper footing?
Even IF that was the case, I THINK it is incredibly near sided to go through all that work and limit the utility of your slab that way (placing just two specific load footers)
No ones imagination is going wild, I would argue that the only imagination going wild would be yours. Its ALL a matter of opinion. To me, you thinking he MAY have to pour a footer for the proposed changes sounds as crazy as my ASSUMING there is a footer sounds crazy to you.
Dont know if James is still following up on this but maybe next time he posts he will be a little more specific to avoid SO much assumption...
Sorry, it's not a matter of opinion my friend. Try again
mark122 wrote:
To me, you thinking he MAY have to pour a footer for the proposed changes sounds as crazy as my ASSUMING there is a footer sounds crazy to you.
Mark, I'm happy to go there with you....
My basis for stating that he may have to pour an adequate footing for a relocated point load is based on fact. If you were building this structure with proposed changes from scratch and getting it through plan review, it would indead have to have an adequate footing which would NOT include a 4" slab on grade. I'm not saying that there is only a 4" slab on grade where he would like to move to post to, but I have seen zero evidence thus far stating that it is not. Additionally, it is quite common to pour concrete approx 4" thick on grade in areas that are not supporting concentrated point loads and my assertion (not assumption) has ample construction precedence. Thus, to state that he 'may" have to pour a new footing hardly constitues crazy talk.
However, your assumption that there is already an adequate footing in place for proposed changes is based on idle conjecture lacking any evidence or common construction precedent whatsoever. That's crazy talk.
Right, just like my basis for saying he doesnt need to pour a footer is based on fact. If there is no footer, one is needed, If there is a footer, nothing further is required.
Dont understand whats so hard to understand here. I said, assuming he does not have to address the slab, this could be his course of action. I see a building standing for 21yrs without a crack in it (based on the comment no structural issues), I am going to assume whoever poured it wasnt a cheap bastard and opted for more than 4''of concrete when planning on parking (possibly) 2 heavy vehicles- rv and truck to haul it.
Again, you gravitate to presuming that this case is the worst case scenario and I dont. I presume based on what my practice is. In my opinion that minimum requirement is to "minimum". When I have pour slabs that have one side that is used as an entrance to the building, even if there is not a point load on the slab, I pour a footer. Call it what you will, this is the kind of thing I do.
So i guess in the atempt to shoot this lame horse, let me refrase.
Based on my understanding of you description, the condition of the building, and "my" EXPERIENCE: If you have a slab that has a proper footer where you propose to make your changes...(see original comment and recommendation)
try again....
mark122 wrote:
Again, you gravitate to presuming that this case is the worst case scenario and I dont.
No. I gravitate toward providing what is necessary in order to pass plan review and obtain a building permit for most juristictions. Plan review does not allow for unsubtantiated assumptions. You either prove existing conditions meet structural code (perhaps by excavating*) or provided structural details that provide for it regardless of existing conditions.
If I were assuming worst case scenarios (as you assert) then I might have mentioned the necessity for designing the new post footings to cover inadequate soil bearing conditons. I didn't.
* not indicated on O.P. post or photos
deadnuts,
IRC does not regulate or pertain to nonhabitable structures.
KK
Prove it.
Here's where you're (albeit inadvertanly IMO) right: The IRC does not regulate nonhabitable structures, per say.. For that matter it does not regulate habitable structures. What the IRC does is establish a comprehensive set of residential building codes that building departments in local juridications can choose whether to adopt--or not. If adopted, the IRC includes provisions that allow for regulation. However, it is local building departments that do all the regulating. In fact, provision R104.3 of the IRC states: "Notices and orders. The building official shall issue all necessary notices or orders to ensure compliance with this code."
...and here's where coonass is wrong: Unlike his assertion that it does not, the IRC does pertain to this nonhabitable garage structure. Why? Well, most local juridictions require a building permit for accessory buildling structures of 200 square feet or more. This includes most workshops, sheds, and garages. And the most widely adopted residential building code in the world (including most of the U.S.) by local building departments is the IRC. Thus, it most likely pertains to the garage in quesiton-- and is probably why this non-habitable accessory building structure (which is clearly in excess of 200 sq. feet) will require a building permit for the structual changes being considered by the O.P.
I'll point out that we haven't head a peep out of Opie. It would be nice if he told us where (what climate) this is, what he knows about the slab, etc.
Btw every nut and bolt and connection on the twin towers was designed and approved by engineers Engineers designed the bridge in Washington that swYed so badly in the wing that it collapsed and there are thousands of buildings in this country that are hundreds of years old that were built by uneducated people
...and what does all this drivel have to do with the price of eggs in China?
The point of the post is fairly clear. Having engineers involved guarantees nothing....except that the OP would be out a likely $1,000.
Who said anything about guarantees (besides you) ?
clear as mud
cussnu2 wrote:
The point of the post is fairly clear. Having engineers involved guarantees nothing....except that the OP would be out a likely $1,000.
Doesn't "guaranteeing" a "likely " anything in one continuous sentence constitute an oxymoron? At least that much seems clear.