Changed my original plans of using gravel boards. And I've decided to use Rsj and sleeper combo. Rsj cemented vertically into the ground then sleepers slotted in. The sleepers I've looked at are 200mmx100mmx1.2m. I don't know what size Rsj to use. 152x152x23kg? Issue being a 5cm gap. Would you suggest using this and packing them out at the back to push them flush? Could use Packers they use for pvc window installation? Or is there any size Rsj you could suggest using? Any help would be appreciated. Thanks (Posted in landscaping aswell didn't know where to post)
Here in Australia our sheds sell 100x100 (to take 75mm sleepers) galvanised H-sections in varying lengths specifically for this purpose. Not sold in UK? https://www.galintel.com.au/products/retaining-wall-posts/
Yes, but the Aussie ones are supplied in a variety of lengths and are hot dip galvanised after cutting so should have a much longer life than painted ordinary mild steel.
How high is wall? What kind of soil? You probably don't need a lot of strength in the steels as you're going to have them at fairly close centres. 125x76 UB will probably do you
Yes, the most likely point of failure is the posts shifting because they're not deep enough in the ground. Here our rule of thumb is as much below as above, though what's necessary is obviously a function of the soil type. In firm clay a post hole borer is the way to go. And make sure that there's suitable drainage at the base of the wall.
Yeah my plan was to purchase 1800mm beams. What would your suggestion be regarding the Rsj sizing? Because I don't want to spend money on Rsjs which are over kill in size , leading to higher costs. Been looking at Jarrah wood sleepers or hardwood tropical which are 125 thick. I assume better and longer lasting than standard pressure treated soft wood.
A 152x89 UB would take the 125 thick sleeper. Extra cost around £10/ beam. Alternative is to stick to the smaller beam and notch the sleepers to suit
Thanks for the advice think I may opt for 152x89 ub. I'm probably overthinking it anyway. People use wooden posts which I assume are inferior to and form of steel work.
Did you use Hi. Did you find a supplier for RSJ fence posts? I can’t find anything in UK for end posts or corner posts (like Aussie Retain-It system) made for a sleeper wall.
Any decent fabrication place will make what you want. Use chanel for ends, two chanels welded at off set for a corner
Hi mate. I didn't go down this route as in the end the cost became more than I wanted to spend for the amount I needed. Steels alone were approx £1-1.5k that was to have them powder coated also.