junglejim

I’m wondering if there’s any mileage in filling the base of the RSJ with mortar? But probably not ideal from a cold bridging perspective.

Here’s a photo of how it is currently. Will obviously need to dig out the ground as well.

Figured a drawing would be useful as still a bit unsure of the best way to finish this. Thanks for all the tips.

Slightly concerned this could be a way for moisture to ingress (around edges of the RSJ) any tips on sealing? Considering expanding foam + mortar to fill gaps.

Thanks, that’s useful. The side facing outwards is the ‘I’ shape so not a face. I’m thinking of insulating, adding noggins and then osb with dpc over but wondering if I’m better off covering in render board and extending down to overlap the slab?

The upstand around our slab is cut for RSJ to fit into at slab level. I’m wondering how best to finish the exterior around this as will be closer to ground level and below the cladding. Presumably it could somehow be sand cement rendered? Thanks

Update: Thanks for everyone’s thoughts and advice. Below is the reply from the engineer today. Feel much better having this in writing but still a little weary given the concerns raised on here. “I can confirm the 140mm long Rawlplug screw with plastic plug is the preferred fixing for timber sole plates to concrete up-stands. This type of fixing alleviates any excessive lateral forces within the up-stand unlike an expanding bolt fixing.”

I used a hammer tacker in the end… really easy and quick to use… found it invaluable.

Thanks. Haven’t spoken to SE yet but will do. The drawings specify shot fired. I think there were concerns though about that being risky as could damage the concrete with that method…. My gut feeling is in line with people’s thoughts on here that the plastic plugs are not a good enough alternative but definitely need it checked. Going to be quite a bit of work to remedy I suspect but need the house well anchored!

Thanks for the comments. No this is a concrete raft slab with timber frame on top. The external face of the upstands/slab is going to have a render finish. We are cladding above that. just out of interest what kind of fixings would you expect on this? Anchor bolts?

Yes I share that concern. I’ve been around the perimeter and checked the concrete. As far as I can tell it’s blown in 3 locations so the rest seem good. Not sure I can remedy the anchoring at all as the building is up and fixed to the sole plate. I’m not sure why they’ve used plastic plugs. Engineer drawings specify shot firing (I’m not sure what that is) I’m speculating but wondering if shot firing would have been more likely to damage the concrete? I don’t know if there are frame anchors as well… but of a can of worms here and not sure how to broach with the company 😬.

Thanks yes tempted to just crack on but obviously a critical part of the building so want to make sure it’s done right and water/weather tight. I’ve come across a couple of products. Is this the kind of thing you’re meaning? Fibromix 40: https://www.waterproofingaccessories.co.uk/product/fibre-reinforced/ Resincoat: https://www.resincoat.co.uk/en/home/454-resincoat-all-in-one-concrete-repair-mortar.html cheers

Hoping that this is repairable with some kind of mortar but worried it might be a weak spot so want to make sure it’s done right.

Thanks… that’s good to know… do you think I’d get away with one strip or need to do lots of short sections like the plastic one?… advantage of short ones is that they could be slid beneath the tile which will help hold in place but would require much more lead. The presumably would also need a side fixing to the barge board or batten… struggling to find information online about doing this.