DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Building & Construction (
-   -   Ceiling/Floor Joist Size and Space (

charlie58 04-19-2010 08:56 PM

Ceiling/Floor Joist Size and Space
This is my first post and my first attemp at a major project.
I am building a room inside a steel building (shop). The room will be 12 ft. X 20 ft. One of the 12 foot walls and one of the 20 foot walls will be screwed/attached to the steel beams of the steel building walls. I will have a drywall ceiling inside the room and will deck the top of the ceiling for storage space. What I was needing to know was that since the ceiling joist will be used as the support for the drywall, insulation, decking on top (floor) and then storage on top, what size joist and what spacing should I use? Oh, the joist will span the 12 ft length not the 20 ft length. I want to be able to support a reasonable amount of storage weight in top. Naturally, this is a flat ceiling. Any help would be greatly appreciated.

charlie58 04-27-2010 01:11 AM

I asked this question back on the 19th and never got a response. Could someone reply or at least let me know if I should not ask these types of questions here so I could try to get the answer somewhere else? Thanks

Scuba_Dave 04-27-2010 07:33 AM

Using it in a shop for storage above I would use 2x12's 16" OC

wjackson91 04-27-2010 08:16 AM

Hey! First post here, but I've been do research for a shed I'm building and had some of the same questions you have. I found this calculator at the following link to be helpful.

You can input the type of lumber, the load, and it will give you the maximum span. You can also reverse the calcualtion by using the "Span options Calculator..." under the calculate button. Once you input the lumber type, load, and span it will give you options for what lumber to use.

Hope this helps!


jogr 04-27-2010 03:10 PM

Using the calculator wjackson linked 2x8s, 16"OC in #2 Hem Fir spanning 12' would hold 40 pounds per sq ft which is a typical minimum for residential construction. That would be 9600 lbs in your 12x20 loft. And since it's just for storage you're not going to be concerned about a little bounce when you walk up there.

All times are GMT -5. The time now is 04:49 AM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1