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I have very good building experience but in a house we bought recently I have been wondering what the heck to do with my loft. Initially its converted to a mini workshop / storage

The max height is 1.8m from the floor boards to the centre of the roof. I stand up straight just about. The previous owners laid down some off cut planks to make the loft walkable.

Ideally I would like to lay proper pieces of plywood and make the entire central area flat so that I can get in the loft, sit on a chair with wheels and wizz from one end to the other.

Problem is these weird beams that run left, centre and right of the roof structure. OK- initially you think yea these are support beams- but they do not lie within the masonry structure on either end- and are really badly joined in the middle- as if temporary. These beams are screwed ONTOP of the actual support trusses that all the planks are screwed on to and the ceiling batons are right at the bottom.

Half of the loft with the joined "temporary" beams shown.

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A closer look at the central beams- You see that they are screwed on top of the support trusses and nothing else touches them.

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Another close up at an angle of something like 45 degrees

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Apologies for my terrible representation here.. but its just for illustration.

  • RED - The central beam that is top most
  • BROWN - The cross load bearing trusses that lie on top of masonry in the supporting structure. I can stand on these they will not collapse.
  • GREEN - The house perimeter- masonry load bearing walls

I am not interested in removing the left and right beams as they are in a tight spot. I will build cupboards there later on or something.

I know from experience I can remove this beam with out the house collapsing. But, I wanted to confirm it here with other experienced people, as I have never seen anything like this and I do not know why its there and if it serves any structural purposes.

Can I remove this beam (the 2 beams joined up)?

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2 Answers 2

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I think they're there for stabilizing the brown beams/joists. Typically, a loft is unused space with no floor. Between the joists, there is insulation supported by drywall or other material depending on the age of the house (as in pic 2 and 3).

Typically one would put in blocking between joists to stop horizontal flexing and torsion.

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Since an attic is usually unused space, I think someone took a short cut and just screwed the 2x4s to the tops of the joist. (Significant labour savings!). Your flooring probably makes it unnecessary from a flexing point of view, but you still have a torsion problem (especially since you're now loading the joists).

When you go to make improvements, block the joists properly, but I wouldn't worry in the short term.

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  • Yea- I will put proper blocks in. I will also have to look into the extra load now. I might have to run extra trusses if I can to help support. It seems the gaps are wider than usual.
    – Piotr Kula
    Commented Aug 2, 2012 at 15:54
  • PS How can i roughly calculate how much load they will bear. I never had to calculate that before.
    – Piotr Kula
    Commented Aug 2, 2012 at 15:56
  • There are 3 bits of info you need: Dimension of joist, Spacing, and span. Commented Aug 2, 2012 at 16:01
  • Ya- I can get those.. So how do I calculate a safe load.
    – Piotr Kula
    Commented Aug 2, 2012 at 16:03
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    Live load = 40 psf. Dead Load 10 psf. Deflection Limit = L/360. Plug it in here, along with the measured parameters, Use Spruce/Pine/Fir as the wood (weakest) unless you have actual knowledge. This will tell you the maximum span those joists can support. awc.org/calculators/span/calc/timbercalcstyle.asp Commented Aug 2, 2012 at 16:13
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I'm guessing it's there to keep the joists evenly spaced and to prevent warping during construction. This is important when you're drywalling. Otherwise, the edge of the drywall wouldn't line up with the center of a joist and you'd need to sister in a nailer to put up the drywall.

It could also be there to give added stability so the joists don't tip over, but this is often done with blocking or cross pieces between the joists. Blocking in a few places and a beam may give you the same effect, but I'd upgrade it to proper blocking.

If you remove the beam, you may see cracking in the drywall as things shift. Otherwise, I can't think of anything else that could happen, but that doesn't mean I'd recommend removing it.

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  • Yea I also thought it is to stop warping.. but in every new build I participated in we never used beams like that. Its odd. I am going to remove the beams- But I will place blocks of wood in between to replace this bulky beam.
    – Piotr Kula
    Commented Aug 2, 2012 at 15:50

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