Advise on beefing up the loft floor

3 Oct 2019
Reaction score
United Kingdom
Hi all, looking for a bit of advise and hoping someone can help. My loft has been boarded out by the previous owner and they don't seem to have done a good job of it. The joists are 3 x 2 and when I walk in there I can feel it flex and the ceilings below have cracked. I only plan on using this for a bit of storage space.

From what I can see there appears to be 3, 3x2's that run the length of the loft (approx 15ft). Screwed / nailed to the underside of these appears to be a series of more 3x2's that hold the ceiling. Someone has put chipboard on top of these and called it a day. Leaving the three 3x2 lengths protruding obove.

There are also some large timber beams that run the length above the floor at approx 45 degrees. Picture below to help illustrate what we currently have.


I have seen this post which mentions gluing and screwing an additional 4x2 on top of 3x2. With just having the 3 beams running the length of the loft area is this a viable option? I could do that, add some 4x2 noggins and board over? As I say this is only ever going to be used for light storage. But needs to stop the ceilings cracking when I walk around in there and feel a bit more robust.

Sponsored Links
Adding the joists should stiffen them. The 45 degree timbers are probably purlins which strengthen the rafters.

Posting some pics would help clarify.

Hi all, back again this time with some pictures.

Here is one of the joists that runs up the center of the loft. There is also one either side of this about 1.8m apart at the sides of the walls. These three jousts rest on brickwork.

Here is is again. As you can see the other timbers run underneath it.


Now my question is. If I add say 4x2's on top of these three lengths. What is the best way to add additional lengths to support the new boards on top? Add some perpendicular?
Those 3 on top are ceiling binders not joists. Have you got any load bearing walls underneath? You've already got a fair bit of extra weight up there from the DIY loft conversion.
Sponsored Links
There are walls underneath but I don't know if there load bearing. The middle binder which is in the picture feels solid when walked on. So presumably it's resting on a wall.

All those materials from the previous owners conversion are being stripped out. All that will be left is a floor which can hopefully be made stronger. Someone has suggested hangers from the rafters as there are currently none.
Another idea.. Can the three binders be beefed up and then new joists run between them and boarded over? Seems like it might be a lot easier way than trying to beef up the 3x2's that are underneath. Not sure how that would affect weight distribution though?
You really need to determine whether any walls below are load bearing - clues are the wall continuing down to the ground floor and sounding solid when you knock on it, or ends of ceiling joists sitting on it. If the binders span 15' clear then you will need massive timbers to beef them up in any significant way.
Usually there will be a central "spine" wall which can be used to reduce the span front to back.

You also need to see what's behind those stud walls, that might be where your ceiling hangers are?

Best case, you fine a nice central spine wall, remove the "loft conversion" and reinforce the ceiling joists front to back as per your post above.

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local