# Building raised attic floor question



## nocarters (Mar 26, 2012)

Hey gang, first time poster here. Got what will likely be a simple question. I want to build a raised floor in my attic, such that the floor covers the exposed ducts. If I lay 2x6s on their side on top of the existing joists that would give the clearance necessary. Is that safe? Should I instead sister 2x10s next to the existing joists? Hopefully this makes sense. Thanks in advance - Dave


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## joecaption (Nov 30, 2011)

What's there now for joist? Is it trusses or site build rafters?
Lot's of times an attic was not built for anymore then light storage and can cause damage to the ceiling below if this is not done right.


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## M3 Pete (May 10, 2011)

I have done this, and there were a lot of issues. 

But as joe asked, you have to determine whether you have trusses (looks like a bunch of "W"s crisscrossing the attic space), or a "stick built" frame.


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## nocarters (Mar 26, 2012)

*Building raised attic floor*

Thanks guys. The house was built in 1986 (Apex, NC). I'm pretty sure it's or a "stick built" frame - I'll confirm the size of the joists tonight. I'd curious what the issues you had were. Thanks again.


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## nocarters (Mar 26, 2012)

*Help with raised attic floor*

It's site built, not trusses. I guess the question is do I lay the new joists parallel or perpendicular to the existing 2x10 joists?


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## M3 Pete (May 10, 2011)

What is the joist spacing? How long is their unsupported run?

If you have 2x10, why do you need additional height for floor?

10 inches of fiberglass is r30


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## nocarters (Mar 26, 2012)

I want to raise the floor to cover exposed duct work in the attic - currently this lies on top of the existing joists...


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## M3 Pete (May 10, 2011)

is the duct work parallel or perpendicular to the joists? Or both? 

a 2x6 is 5.5 inches tall (wide), will that clear the ductwork?

If you can lay plywood on the existing 2x10's, you might be able to build some 3-sided plywood boxes to cover the ducts. Depends on how many ducts and how they are spaced. 

A 2x10 is a substantial ceiling joist, but we still need to know the spacing and how long the unsupported runs are.


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## AndyGump (Sep 26, 2010)

nocarters said:


> I want to raise the floor to cover exposed duct work in the attic - currently this lies on top of the existing joists...


What is the purpose for covering the duct work?
Are you planning to use the floor space as living area or storage?

Andy.


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## nocarters (Mar 26, 2012)

*Raised attic*

Thanks for all the replies. The raised floor would be used just for storage - mostly lightweight (no old barbell sets etc...). From time to time I'd walk on it just to add or remove items. I'll try to answer the other queries tonight from home. Thanks again all!


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