How Much Weight Can Attic Support? (Explained!)

Whenever I have extra valuables to store up in my house, my attic is the first place that comes to mind. This storage space has saved me several times from having my bedroom or kitchen cluttered with extra stuff that I don’t usually use.

Whether you use your attic as a storehouse like me, or you use it as a guestroom, bedroom, or even a reading room, you must ensure that you do not place too much weight than it can support so the floor of your attic does not collapse.

In this article, we will take a close look at how you can determine how much weight your attic can support.

Weight Can Attic Support

here’s how much weight can attic hold:

Attics come in various shapes, terms, sizes, designs, and layouts. So it is not easy to give specific details on how much weight it can hold.

But if we want to predict or estimate it, then the size and thickness of the wood used in making the floor joists of the attic is always a useful guide.

  • If your attic floor is made of 2×4 wooden joists, then it can hold the weight of people under 150lbs.
  • If your attic floor is made of 2×6 wooden joists, this should provide extra protection of about 40lbs so that it can comfortably support people whose weight is under 190lbs.
  • If your attic floor is made of 2×8 wooden joists, it will support a weight of over 190lbs.

Since most people averagely weigh more than 190lbs, it is often recommended that the wooden joists of your attic floors must be at least 2×8 thick.

Other things that might influence the amount of weight that your attic can hold include the quality and age of the wood.

How much weight can you put in an attic?

As useful as attics can be in your home, you must be careful so you don’t put in too much weight that will damage it and destroy the beautiful structure of your home.

The table below will give you the likely average weight load that your attic can carry, depending on the thickness and dimension of the floor.

Floor Joist DimensionsEstimated maximum weight per square footSuitable purposes
2×4 inches10lbsStoring empty boxes
2×6 inches14lbsStoring light items
2×8 inches18lbsStoring heavy items
(Note that “lbs” is the same as “Pounds”)

In case you never really took note of the dimension of the floor joists of your attic before deciding to convert it to storage space, you don’t have to panic.

It might be safe to store a 10lbs load in an attic that was never designed for storage initially.

If it appears your attic has a limited storage space, it might also be safe to not store a load of more than 20lbs.  

But whether you know the dimensions of your attic floor or not, you must ensure that you do not make your attic carry more than these recommended weight loads so that you don’t injure yourself or damage your property.

Can an attic support your weight?

If you want to know if your attic can support your weight, the best way to go about it is to contact a professional contractor or a structural engineer.

(The only exception to this is if you have a lot of experience with building protocols)

You may assume that your attic will support your weight if your floor joists are strong enough and at least 2×8 inches thick.

But this is still not advisable as an attic that has supported your weight in the past might get damaged due to water and moisture before the next time.

How do I know if my attic supports weight?

Mostly, the structure of the floor of the attic goes a long way to deciding the kind of weight it can support.

So if your floor is old, then your attic is more likely to collapse underweight. Also, if your floor is new, it is less likely to warp and will withstand more weight.

Another thing to look out for is the capacity or size of your attic, and the construction material used in making the attic.

But your best bet is still to consult with a professional contractor or a structural engineer, especially if you do not have building experience.

how much weight can attic beams support?

The amount of weight that attic beams can support is determined by local building codes. But it is mostly influenced by whether it is carrying live loads or dead loads.

Typically, most attic beams are designed to carry live loads of at least 40lbs per square foot and dead loads of about 10lbs per square foot.

how much weight can attic trusses support?

If you want to know the weight that your attic trusses can support, then you might need to check with your local building codes. But there are estimated values that you can always follow.

Typical truss systems are made of 2×4 joists, and these attic trusses are estimated to support about 10-12lbs.

If you have a truss system with higher thickness, then it will most likely support a higher weight. For instance, a 2×6 truss system should support about 12-15lbs.

So it is safe to say that the thickness of your truss system is a great determinant of the amount of weight that your attic trusses can support.

how much weight can my garage attic support?

The best way to determine how much weight your garage attic can support is to check with the local building codes. But this would only be appropriate if you followed the codes when building the garage.

So if you didn’t follow it, you might have to consider other factors to determine how much weight your garage attic can support. Some of these factors include live load, dead load, strength, stiffness, span tables, etc.

Many times, these local building codes will follow the International Residential Code (IRC), and they determine the weight your garage attic can support as a measure of the live load capacity.

According to the IRC, if your garage attic is for non-sleeping areas, then it should support a weight (minimum live load capacity) of about 40lbs per square foot.

Similarly, if it is built for sleeping areas, it should support a weight of about 30lbs per square foot.

Another factor to pay attention to is floor deflection.

According to the IRC, this cannot be more than 1/360 of the total floor of your garage attic.


Whether you are looking for a new guest room, bedroom, reading room, or storage space, your attic is your best bet.

But you must ensure you do not place more weight on it than it can support so you don’t end up damaging your property.