The quick answer...
Posi-Joists cost from around £25 ex VAT to over £200 ex VAT per joist.
What are the variables?
The cost of your posi-joists depends on a few key variables: the joist depth, the span of the joist and the spacing.
Depth: If you plan to use posi-joists to construct a building that will house a gym on the second floor, for example, you'll need a deeper joist to support the increased load. The same logic applies if you're building a block of flats or fitting underfloor heating. More weight = deeper joist, increased cost.
Span: If you hopped over to our shop page and looked at all of our posi-joists, you could purchase one that'll span up to 2m for just £24.58 ex VAT. This isn't going to cut it for most homes though, so let's say you needed to span 7m—this would cost you £151.81. The depth naturally increases and the spacing decreases the further the joist needs to span; this pushes the price up. If you can utilise internal walls as support, you can get away with using a shallower, shorter joist; granted in higher quantities. Which one is cheapest will vary from project to project, but it's worth looking into.
Spacing: Spacing the joists further apart (600mm) means there will be fewer overall joists and increased load per joist, so there may be a need to increase the depth. Spacing them closer together (400mm) means you'll need to purchase more joists, but they won't need to take as much load per joist, resulting in a potentially shallower joist. Which is cheaper, again, depends on the project.
I have a 3 bedroom detached house, how much will Posi-Joists cost?
This is one of the most common home types, so let’s price up how much it might cost to manufacture posi-joists for this example. The average UK home is 76m/sqm; for this example we'd need 35 posi-joists at 253mm in depth, spaced 600mm apart. This would result in a total cost of approximately £1500 ex VAT. Please note this is excluding delivery, so add on a percentage depending on how far the products would need to travel.
When you opt for a design with us, we can sort all of this for you and provide you with the most cost-effective option for your application. Please get in touch if you've got any questions; either via live chat on our website, by emailing us or picking up the phone the traditional way.
p: 01432 355046
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