Flooring in attic w/blown-in insulation

[nutsnbolts]

I am trying to find ways to create more storage in our townhouse so that the garage can be used as my shop only. Currently the garage has all of my tools, plus a bunch of **** that has nowhere else to go. One solution I have considered is putting flooring in the attic and storing boxes up there. You know, Christmas and Easter and camping gear, luggage, that sort of thing. If done properly there is a lot of space up there. But I have a few questions...

The attic was insulated with blown-in insulation. It is overflowing above the floor joists. If I want to put plywood down, can I compact that insulation, or do I need to clean out and throw away the excess?

What about venting? Would sealing up the insulation in this manner cause condensation problems? We live in Seattle, it is a drizzly climate.

I have about 10 sheets of plywood, I think they are about 3/8" thick or so. Is this sturdy enough for me to then walk on? (250 lbs) I don't have a use for it, so this would be a great project for it.

Any other things I should consider?

 

[bad_idea]

If you compress or remove the insulation you lose it's insulating capability. Also, the attic is likely not rated for the weight. Just the weight of the plywood could cause the ceiling to sag, let alone whatever you store up there. The PO of my house stored **** above the garage and the ceiling is now sagging and cracking. Glad it isn't in my living room.

 

[nutsnbolts]

If you compress or remove the insulation you lose it's insulating capability. Also, the attic is likely not rated for the weight. Just the weight of the plywood could cause the ceiling to sag, let alone whatever you store up there. The PO of my house stored **** above the garage and the ceiling is now sagging and cracking. Glad it isn't in my living room.

That's good to know. I'm not really concerened about losing some of the insulation...our house is over-insulated, if you ask me. We never turn the heat on in the winter and many times we have the AC on if it is over 50* out.

How could I go about figuring out if my attic could handle the weight?

 

[4cyclic]

compressing cellulose you will not lose r value, but I would also be concerned with ventilation and joist capacity.

 

[sublime68charger]

what is the size of the floor joist?

what is the spacing between them? Joist to Joist?

how much distance are the spanning?

what does your rafters look like?
is there room between the braces to put down your plywood sheets?

some Pics of the attic area would help?

 

[CNGsaves]

Build a storage shed in back yard.

Many GJ threads for great builds. Gambrel style roof will give you lots of storage in loft/attic of that shed for all those decorations, etc. that are bulky but not weigh much.

Also could give you spot for lawn mower and misc lawn equipment/tools so you could get those out of garage as well.

 

[nutsnbolts]

what is the size of the floor joist?

what is the spacing between them? Joist to Joist?

how much distance are the spanning?

what does your rafters look like?
is there room between the braces to put down your plywood sheets?

some Pics of the attic area would help?

I will get up there and take a look at it again and get that info. I am at work so I cannot go check right now. And I will take pics for sure.

 

[rsanter]

Look,at your flor plan, the location of the walls.
Do not store anything over a long span of a room.
If you have a section where there is good support due to rooms below then put the plywood there and use that part for storage.
I did this in a previous house and had no problems

Bob

 

[LB-1911]

what is the size of the floor joist?

what is the spacing between them? Joist to Joist?

how much distance are the spanning?

what does your rafters look like?
is there room between the braces to put down your plywood sheets?

some Pics of the attic area would help?

I will get up there and take a look at it again and get that info. I am at work so I cannot go check right now. And I will take pics for sure.

I'm pretty sure once you get up there you'll find out you have trusses.

Don't be surprised if the bottom chord is a 2x4 & they will be spaced @ 24" on center.

 

[Big Bad Dad]

Standard roof and ceiling trusses are NOT rated for an attic floor load. Be carefule, sounds like you are headed for trouble. Get an experienced Carpenter to advise you.....

 

[Hpozzuoli]

Don't pack the insulation down. Compressed insulation doesn't insulate as well. Also if the heaps are higher than the joists you risk pushing the insulation thru the ceiling. Just screed over the joists with something to remove the high spots then drop some plywood. This is probably a 30 min project. Don't make it any harder.

 

[nutsnbolts]

Build a storage shed in back yard.

Many GJ threads for great builds. Gambrel style roof will give you lots of storage in loft/attic of that shed for all those decorations, etc. that are bulky but not weigh much.

Also could give you spot for lawn mower and misc lawn equipment/tools so you could get those out of garage as well.

There is no back yard, nor a lawn. We have a small patio in back that we can entertain 6 or 8 people on.