Timber framed residential garage floor 1

[m_struct]

Looking for recommendations on timber framed floors in a residential garage - ie design for high point load.

What floor systems is typically used? 1.5 inch decking? Is there a rule of thumb on the joist spacing? Note that cost efficiency is important here.

 

[jayrod12]

For most wood framed floors on garages I try to get the wood trusses constructed as attic trusses. But that depends on what a high point load is, where it could happen, etc.

If you're talking heavy timber floor, that and cost effectiveness are rarely used in the same sentence.

Edit: Just realized that you're talking about parking on timber.

I agree with the below posters, I'd be looking at 3" decking if you're really set on using a timber floor, but I agree that timber floors for parking is not recommended.

 

[XR250]

2k jack load is going to be tough. Probably need 3x decking minimum. No rules of thumb - just need to do the math.

 

[ChorasDen]

What code reference are you using? IBC has different point load requirements for garage floors than IRC. Individual states also may have additional design requirements for garage floors as well.

Generally speaking, with the weight of vehicles today, I would not be comfortable designing for less than a 3kip point load that can be located anywhere within the garage space. Is this a single car or double car garage? May need to have multiple large loads on a single member if it's double car. Minimum deck thickness of 1-1/8" will be critical here. Can you specify a steel mesh within the poured over concrete to help distribute load across multiple joists?

I tend to recommend against wood framed garage floors, moisture intrusion is going to happen, probably sooner rather than later. How will you detail where the exterior driveway meets the garage slab, how will this be waterproofed, and how will it be maintained through freeze/thaw?

 

[KootK]

Precast plank is commonly used for garage floors. I've seen a few Hambro and composite steel beam setups. Were I cajoled into doing it in wood, I'd likely push for a reinforced concrete topping spanning between -- possibly -- wood framing members, similar to ChorasDen's recommendation. CLT or NLT might be more suitable but I doubt that's the kind of "wood" that your client is looking for. And, even then, it would be a bit sketchy from a durability perspective. I'd not want my garage floor to wind up looking like a bunch of greasy railroad ties over time.

 

[Celt83]

Assuming your talking about a home garage review APA - E440 (should be a free download): Link

My Personal Open Source Structural Applications:

https://github.com/buddyd16/Structural-Engineering

Open Source Structural GitHub Group:

https://github.com/open-struct-engineer