joist strength

Hi, I’m installing a sedum roof onto a 20 sq m garden room GRP flat roof. A common system seems to be: drainage layer on the bottom, then substrate, then sedum roll on top. But some companies sell a lightweight substrate roll e.g...

We are renovating our ground floor kitchen in Edwardian (1930s) house in London. No extensions/structural/notifiable (as far as we know) work planned, just new flooring and kitchen units. Whilst pulling up the old kitchen and flooring, the builder has highlighted that the current flooring is...

Hello, I'm just wondering how to tell if the joists in your loft are strong enough, whether just for storage or to use as a regular room? I'm partly asking because we would like to eventually board the loft void above the rear part of our Edwardian house to use for storage, after insulating...

Hi, I recently lifted my floor in my bathroom. I inspected underneath to discover the end of my joists look wet. I can't reach that far to inspect, it seems to be all 3 joists that I can see all which are on the external wall side. All floorboards above are dry. I have attached a pic. Anyone...

Hi Everybody, I'm in the planning stages of upgrading an already converted loft (pre-regs, very little insulation etc) so that I can legally class it as a bedroom. I've paid the fee to Building Control and the surveyor has made their initial visit. I'll be using SuperQuilt for the insulation...

Hi all. I'm new here, please go easy on me. I need you all the chippys, architect and builders advice on board and ASAP. I've removed my chimney breast walls from top to bottom. I'm now left in the bedrooms with exposed Joists, which are 7x3 timber and 5 metres long. I was hoping, is it...

Hi All, I am doing up our new but 50 year old dormer bungalow and need some advice on the floors. The upstairs floor is sagging and appears to have undersized joists (16" centres, ~5.2m span, 2x7" joists). To complicate matters, the area is divided by two partition walls (bathroom and...

I am putting a new flat roof on a brick built garage, stage 1 is to get the roof watertight and stage 2 next year is to make it into a green roof, probably sedum. The garage is approx 5.25m x 3m with joists to run across the width (3m) I have been looking at some of the weight considerations...

Our Victorian property has a flat roof side extension for the kitchen. The kitchen ceiling is in part under the original property and in part under the flat roof. A long RSJ props up the original wall of the house. We are going to fit a ceiling extractor above a new kitchen island. The...

Hi all, Starting a new thread as the older problem has morphed slightly. To recap: 22mm square-edged boards are going down first, then 18mm solid oak hidden screwed on top. However, after removing some tiles that represented an old fireplace upstairs, I found that there was no joist continued in...

Hi all, I want to replace the banister around my landing upstairs with a couple of stud walls so I can essentially create a separate enclosed space upstairs. Part of the stud wall that needs building cannot be built directly on top of the existing subfloor, as there would not be enough space on...

Hi. I wanted to check out a recommended solution for strengthening my loft joists before boarding. I have a Victorian terrace; 2 external walls with 2 supporting walls running parallel between them (staircase is in the centre of the house); span from each external wall to each supporting inner...

Hello, I'll try to keep it brief: we are having a wood stove installed, and the HETAS approved installer has cut through a joist in the first floor, and a joist in the roof to allow the flue to run up and through the roof (it has an angle in to avoid rafter). There are now two joists (circa...

Hi all, I am looking to board up the loft to a good standard ("proper" and all). Everyone recommends - in order to hold the insulation to raise the floor before boarding. And the best way is to do this is to screw cross-battens into the ceiling joists - (2" by 4" timber battens have been...

So after a long weekend of removing my chimney from the attic and 1st floor I’m stuck! It looks like the 1st floor joists are sitting on timbers that are resting on the chimney. Whats the best way to tackle this? This is a bedroom that is going to be repurposed into a bathroom. Structural...

I need to add more attic storage space, so I want to put a floor down in an unfinished section of the attic. Joists are 2"x6" and 16" on center with 10" of blown insulation. My plan is to strap another 2"x6" perpendicular to the joists giving me 11" of space for the insulation, and then...

'm working on new bathroom on the first floor - we have new soil pipe which comes in through the ceiling in the corner. The way I would want to position the toilet will mean that the joist will need to be cut approx. 6cm in the deepest place. Can this be done ? Is there a way that the joist can...

I have purchased a small terraced house. It is in a linear setout (where each room is behind another, NOT next to each other) i have proposed a plan to install a mezzanine floor above the two bedrooms. for this to happen, i will need to remove the current ceiling. however in doing this i will...

So we had central heating installed and were later told that the plumbers had cut through the joists when they shouldn't have- the floorboards were essentially resting on the pipes etc.... So then somebody came along and drilled holes through the joists under the cuts to feed the pipes through...

Hi All I am planning on building the kids a slightly raised (50cm) playhouse with a walkway, the total distance of the walkway will be 6m, the width of the walkway was going to be about 60cm I was going to use 4x4 fence posts as supports and then bolt 6x2 joists for frame and lay decking on...