My concrete sub poured my garage foundation wall Wed.. I got home after work and checked things out. Everything looked good except for the steel anchor bolts, not the galv. anchor bolts I set out for them to use.
Arrrgh!
Now what to do. I know the new pt lumber says 1/2″ steel bolts are acceptable, but we have already heard some horror stories here about them.
I know I’m not the first to run into this. What preventive measure are any of you all taking to prevent future corrosion of steel bolts?
Dave
Replies
One thing I've heard is that if the wood stays dry it isn't as much of a problem. I suppose though, that is unlikely in a garage. Maybe painting the bolts with something to sort of isolate them from direct contact with the pt. (Maybe something like Loctight? or epoxy, or even caulk?) See what others here have to say.
I remember seeing an episode of This Old House in which Tom Silva used plastic tubing as a sleeve for bolts going through PT lumber.
clean the oil off of the bolts and spray them with Cold Galv.
or drill your own plated or stainless anchors into the concrete.
honestly not that big of a deal.
carpenter in transition
Put the galvanized nuts and washers on the bolts. The washers are ususally the piece that comes in contact with the wood anyway.
I only golf on days that end with a "Y".
drill straight through your plates and use Powerfast epoxy. http://www.powers.com/pdfs/approvals/Power-Fast%20ESR-1531.pdf
we've been using this system for years in high wind loads ( I've just used it for a truss uplift load of 56KN resistence). You will never cast bolts in place again.
Glue-in anchors are very dependent on the care and attention to detail during installation. The holes have to be deep enough and properly sized. Once drilled they have to be cleaned well and prepared. The Epoxy has to be used in the right amounts and proportions. It is difficult for an inspector to tell if all these steps were properly done and so the actual strength of the installation. Some will are talking about requiring the use of a test nut with a plastic washer be used as this gives a recognized proof of strength. One at every anchor in some cases. Other inspectors seem to be pushing for just critical placements and perhaps a representative fraction.Lacking that some inspectors are rating these installations at some fraction of their official rating. Which means you may need more anchors. In one case a contractor got caught drilling the holes just a couple of inches deep. Squirting in epoxy and slipping in a short piece of rod and a nut and washer. It wouldn't have got caught until the inspector noticed that the washers weren't crushing into the plate. He watched as a carpenter tightened it up. The whole bolt came up.The inspector was not amused. This is hurricane territory and anchors are serious business.
Mark, how does the costs compare using the epoxy that you mentioned vs the labor to locate and drill? Your method seems like it would be much faster so the costs of the epoxy could still be considerable to break even.
blue
Blue
typically in a home of about 250-300 sq m we would be installing around 100 1/2" rods. Our costs for epoxy work out at around a little over $1 per hole. Time to drill and blow 100 holes is around 2 1/2 hours.
As our rods are continous to top plate anyway there is no extra material costs. There are no location errors. No set out dramas or labour time.
Our system is faster and cheaper.
Someone raised the issue of correct installation and it is a fair point. If holes aren't blown out and cleaned then you have nil hold down. However this is soon picked up when you tighten down as the rod will just pull out. As I've said before here, under our licensing system we are responsible for our work for 6 years. Tie down is not something we mess with.
regards
Mark
ZRC makes a cold galvinizing compound in an aersol spray and a painted on version. That should protect the bolts although I don't know how that will affect threading on the washers.
Thanks to all.
Now I have options.
Dave
Dave
We cut a piece of 1/2" plastic pipe 1 1/2" tall and put it around BOLTS. Building inspector is satisfied, an easy fix. I use galvanized nuts and washers to finish. I try to keep it simple.
Greg in hot Connecticut