Hi all, I have been asked to put a ceiling/roof on a breeze block office in a factory unit. It's basically been built in breeze block into the corner of the building but has no roof. The owner wants to store things up there. Can I attach joist hangers directly to the existing brickwork & hang the joists from them? If so are bolts better to use as fixings? thanks
It depends on the weight that is going to be stored on top, I would cut out the blocks and build the joists in, make sure they are big enough to take the weight.
i don't think cutting bricks out is not an option to be honest - if you can imagine the office is made of block in the corner of a brick built factory. whilst the joists can sit on top of the block or be hung from them the corner walls are brick - do you mean cut bricks out and sit the joist in them? is there no way they can be hung from the brick using joist hangers & bolts such as these? http://www.screwfix.com/p/fischer-a2-shield-anchors-8-x-60mm-pack-of-5/51645 the weight will be in excess of 100kg
You have to consider that you will be attaching the joists to the high part of the breeze wall which is not supported or held there by anything except itself. I would think far better to have a plate on top, and matching plate, level bolted to the brick walls, hanging the joists from these. Bolting or strapping the atop wallplate will provide rigidity to the walls. Mr. HandyAndy - Really
there are conduits running down the brickwalls with electric cables in them - which made me think that fitting a board along the brick would be impossible. i was going to use joist hangers bolted into the brick at 450mm centres with the joists sitting/fixed on a timber board on top of the breeze block - will the joist hangers hold the weight? I have in the past used wall bolts to fix heavy things to walls such as large plasma screens and cupboards - will this be sufficient?
You could fix along one of the brick walls a 75 by 50 mm timber with the bottom edge level with the top of the block walls then cut a 75 by 50 mm notch on the ends of the joists to fit over the timber. you can fix the 75 by 50 with plenty of bolts to the brick wall. Then the other ends of the joists will sit on the block wall.
ok guys thanks for the input - i really need to get away from the level board bolted to the wall idea - as i mentioned in a previous post there are conduits running down the wall with cables in. If I were to go with the board bolted to the wall approach i would have to notch the board out to make way for the conduits which would make it weak. I take it from your answers of bolting a board to the wall, that bolting joist hangers to the wall will work just as well - probably even better as each hanger would be fixed with 2 bolts & the joist strapped at the other end to the timber on the block wall. Just needed a yes or no to bolting joist hangers to brick as a board bolted to the wall or knocking bricks out is not an option. given that timber to brick/concrete joist hangers are available I think the answer is yes cheers
I would say the most important fixings are the joists on top of the breeze wall. Attached well at each the ends(to the brick wall), attached well down onto the breeze wall, and attached well to each other at the outer corner, then most anything you put inside, be it hangered to the brick or whatever, will not be going anywhere fast. Mr. HandyAndy - Really
Nobody seems to have mentioned building regulations... or planning permission for that matter. I think Building regs would probably expect you to bed and bolt a wallplate on top of the walls, fix the joists to that, and infill or solid strut between them, assuming the roof will be flat. If the roof is flat then you may be able to fix the wallplates out of level to make sure the roof has a fall. I can't remember the regs for flat roofs in detail. You will need to make sure the joists are the correct size, which probably entails either a structural engineer or an architect making drawings. Raising the level of a roof may well require planning pemission, but building regs will tell you - if you ask them... If the roof has to fit inside the walls then take the top course of blocks off on the inner leaf [presumably it has a cavity wall] and bolt the wallplate to that. The wallplate must be strapped at one metre intervals along its length, on both sides. I would certainly check with building regs before starting any work! Don't forget your client may lose out if building regs approval is not granted for work like this, and if it should have planning permission he may be forced to demolish it!.
Well I think the timber bolted to the wall is the easyist way to do it, if you have to notch the timber over the conduits so be it, I did say use plenty of bolts obviousy if there were say 6 rows of conduits coming down the wall it may best not to fit timber to wall and use joist hangers. I have used this system in the past and once the timber is on the wall and bolted its easy to just slap the notched joists on, then move them as you wish to your chosen spacing.
thanks all - the job is done now using bolts & brickwork to timber hangers - too many conduits etc to bolt a timber to the wall I would have used as many bolts as i did in the 8 hangers cheers
Forums
Facebook
Twitter
You Tube
Instagram
Shop