MASA vs anchor bolts
merlinm
| Posted in General Questions on
Today’s footing article (https://www.greenbuildingadvisor.com/article/all-about-footings) was informative.
Our next project will have a slab on grade foundation in central Texas. The structural engineer has provided an option to use traditional anchor bolts or “MASA” (mudsill anchors; see https://www.strongtie.com/mudsillanchors_concreteconnectorsandanchors/masa-masap_productgroup_wcc/p/masa.masap)
We’ve never used MASA before and are looking for opinions on MASA vs. the anchor bolts.
Thanks.
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MASA are a little more forgiving on installation I think, you don't have to mark and drill holes in your PT sill plate for the anchor bolts. As long as your anchors are (roughly) in-line with the footer your sill plate will be (roughly) flush with the outside of the concrete which would make it easier to air seal.
Hi,
I am not a fan of the MASA or holddown straps that are embeded in the foundation and are outside of the building envelope. They are thin sheet metal and will be exposed on the edge of the concrete - this leaves the open to the elements and rusting if not carefully protected.
The anchors are there to hold to house to the foundation! It is important in high winds and earthquakes.
Thanks very much for the answers. We're going forward with 5/8" anchor bolts.
Merlin, or anyone else--you might also consider Simpson's Titen HD anchors. They are drilled and installed after the concrete is placed. You can add epoxy for higher load ratings but in many cases it's not necessary.
Thanks, Michael. We like and have used Titen HD for various purposes, including anchoring. The Titens seem like they may be a little more from a cost perspective -- both labor and materials. The Titens don't achieve load ratings as high as some cast-in-place anchors.
Adding epoxy is an interesting idea. Do you have a link showing the load values for Titens with epoxy? Here are the tables we've used for Titens without epoxy: http://embed.widencdn.net/pdf/plus/ssttoolbox/lgqrhxgcrj/C-A-2018-Titen-HD-designinfo.pdf
Merlin, my mistake--I was going off memory and various discussions with engineers. This is from Simpson's site: "Titen HD screw anchors are not meant to be used with any adhesive. They can be installed without hole cleaning if the hole is drilled a few inches deeper than is required and the concrete is thick enough to accommodate the additional drilled length."
All these alternatives look like a solution in search of a problem. What's wrong with anchor bolts that they need replacing with something else?