joist hangers to existing masonry walls

cubanbetty

ok - ive been trying to work this out and its doing my head in now... I'm putting a dormer in and need to fit new floor joists. The structural calcs have been done and sized based on using hangers.

My problem is my existing ceiling joists are set into the gable walls and central LB wall so to prevent losing stability in the brickwork due to more holes for floor joists I need to use hangers. Can you retrospectively fit these to a masonry wall?



I know the answer is yes but I don’t fancy the ones that don’t have the top plate (I know its psychological as they have been tested in accordance with the relevant BS etc).

So can you take out the mortar above the brick that a hanger woudl sit on, fit the joist hanger and then infil the remaining gap with mortar? Obv leaving it to mature before applying load…


the other option is to fix timber joists to the walls and hang the joists off these but this seems faffy and i'm not entirely sure how you fix the joist to the cavity wall or the party wall becasue you'd use bolts normally wouldnt you?!


advice would be much appreciated! cheers

leveller2911

cubanbetty wrote: »

Can you retrospectively fit these to a masonry wall?



I know the answer is yes but I don’t fancy the ones that don’t have the top plate (I know its psychological as they have been tested in accordance with the relevant BS etc).

So can you take out the mortar above the brick that a hanger woudl sit on, fit the joist hanger and then infil the remaining gap with mortar? Obv leaving it to mature before applying load…



Answer to the first question is yes and answer to second question is also yes.

You need to cut out the pug(mortar) joint on the coarse of bricks your going to "hang" the joist hangers on, only cut out where your putting each hanger not the entire length of the coarse of bricks. Make sure the hanger is straight on the brick if possible and you don't need to wait until the pug has hardend.. If you need to pack each hanger up then use slate under them...

We often use them when we make and fit staircases where the siting of the stairs has changed from original .. We also built our Mezzanine floor in the workshop with them.

cubanbetty

thats great thanks - this is the option I prefer!