Advice on sealing PVC pipe passing through basement wall

[GregPoole]

This isn't strictly a plumbing-specific inquiry, but close enough I hope for some experienced advice.

We recently had a radon abatement company do work on our basement to reduce the radon level. When the tech made a hole through the basement wall to pass the radon venting PVC pipe, instead of doing a core drilling, he just drilled a pilot hole and then impact chiseled through...

I have attached a couple of photos of the finished product. There is some caulking done to seal around the PVC but still left over is about an inch depth yet until the face of the outside concrete wall. The caulk appears to be something like Big Stretch although I didn't see the actual product used.

What would you recommend I use to fill out this area to be flush with the outside concrete wall? One thing I'm considering is hydraulic cement. Other homes in the area have a similar radon installation and it appears they have a tough sealant of some kind.

Thanks for any advice here!

Greg

 

[Slomoola]

Portland cement with sand mix. Mix it up like peanut butter. Trowel it in and brush it clean.

Important, WET the area with water prior to adding the mud.

 

[Sponsor]

 

[GregPoole]

Thanks!

 

[Slomoola]

Another tip is use a cake decorating cone bag deal you put frosting in. Fill it with your mortar mix. Squeeze the bag.......

Again remember to wet the area. A dry area will pull a lot of the water from the mortar mix, not good.

 

[GregPoole]

Thanks. I've got one of those canvas grout bags, like the cake cone bag you mention. Used it in the past to squeeze mortar into brick joints for tuck pointing. Good idea to use it in this case.

 

[louisvilleKYradon]

For filling gaps around radon pipes in concrete, hydraulic cement works well. You could also consider using a high-quality exterior-grade sealant for extra flexibility and waterproofing.

 

[GregPoole]

Thanks for that suggestion.

 

[GregPoole]

Just to close off this post, here's a photo of the finished job. Not a professional here, but I ended up using a mortar mix. It sealed the gap well and now after curing is rock hard.

 

[Fitter30]

Polyurethane caulk​

 

[Slomoola]

Polyurethane caulk​

Some of these are not UV rated. Read the label before buying.