Hi, we'll be installing three steel beams for loft conversion soon & I have few questions to ensure we follow the best practice:
1) Corrosion protection
We're planning to have the steel (S355) painted with zinc primer - is that sufficient?
2) Fasteners (for spliced beam)
What type will be best to reduce the risk of galvanic corrosion - stainless steel, plain finish carbon steel or galvanised?
Also what method is used to prevent loosening of the nut? I guess the risk is minimal as there's no relative movement, but still should play it safe.
3) Gap to outer leaf of cavity wall
One end of the beam is in a cavity wall - what gap is normally left to the outer leaf?
Thank you for your help
1) Corrosion protection
We're planning to have the steel (S355) painted with zinc primer - is that sufficient?
2) Fasteners (for spliced beam)
What type will be best to reduce the risk of galvanic corrosion - stainless steel, plain finish carbon steel or galvanised?
Also what method is used to prevent loosening of the nut? I guess the risk is minimal as there's no relative movement, but still should play it safe.
3) Gap to outer leaf of cavity wall
One end of the beam is in a cavity wall - what gap is normally left to the outer leaf?
Thank you for your help