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mud sill

ICE

ICE

Oh Well
Joined
Jun 23, 2011
Messages
12,910
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California
R317.3.1 Fasteners for preservative-treated wood. Fas- teners, including nuts and washers, for preservative- treated wood shall be of hot-dipped, zinc-coated galva- nized steel, stainless steel, silicon bronze or copper. Coat- ing types and weights for connectors in contact with preservative-treated wood shall be in accordance with the connector manufacturer’s recommendations. In the absence of manufacturer’s recommendations, a minimum of ASTM A653 type G185 zinc-coated galvanized steel, or equivalent, shall be used.


Exceptions:


1. 1/2-inch-diameter (12.7 mm) or greater steel bolts.
  1. Fasteners other than nails and timber rivets shall be permitted to be of mechanically deposited zinc-coated steel with coating weights in accor- dance with ASTM B695, Class 55 minimum.
  3. Plain carbon steel fasteners in SBX/DOT and zinc borate preservative-treated wood in an interior, dry environment shall be permitted.
Notice that the numbering is wrong.

Do you consider the mud sill of an exterior wall to be an interior, dry environment?
 
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I have preservative treated mudsills. Should I be using stainless steel anchor bolts? What about hot-dip galvanized?

The mudsill is a location that is considered dry in comparison to a deck, for example. For wood that is installed and remains dry, the corrosion potential will be comparatively low. Regarding code issues, section R317.3.1 of the 2009 International Residential Code (IRC) addresses fasteners for pressure-, preservative-, and fire-retardant-treated wood; Bolts of ½" and greater do not need to be hot-dip galvanized steel, stainless steel, silicon bronze or copper.

https://www.strongtie.com/products/product-use-information/corrosion-information/pressure-treated-wood-faq
 
ICE said:
R317.3.1 Fasteners for preservative-treated wood. Fas- teners, including nuts and washers, for preservative- treated wood shall be of hot-dipped, zinc-coated galva- nized steel, stainless steel, silicon bronze or copper. Coat- ing types and weights for connectors in contact with preservative-treated wood shall be in accordance with the connector manufacturer’s recommendations. In the absence of manufacturer’s recommendations, a minimum of ASTM A653 type G185 zinc-coated galvanized steel, or equivalent, shall be used.
Exceptions:
1. 1/2-inch-diameter (12.7 mm) or greater steel bolts.
  1. Fasteners other than nails and timber rivets shall be permitted to be of mechanically deposited zinc-coated steel with coating weights in accor- dance with ASTM B695, Class 55 minimum.
  2. Plain carbon steel fasteners in SBX/DOT and zinc borate preservative-treated wood in an interior, dry environment shall be permitted.
Notice that the numbering is wrong.

Do you consider the mud sill of an exterior wall to be an interior, dry environment?
Click to expand...
No
An exterior wall is, by definition, not an interior wall, nor is it a dry location.
That's not dry.
upload_2018-7-25_7-56-2.png
 
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Our Research Section found an ICC answer to the question. The ICC states that it is an interior, dry environment when constructed in compliance with the code. So plain carbon steel nails are allowed.

 
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Exterior walls are not interior, dry locations
And with that theory you would not need treated plates on exterior walls. They are intended to be dry. No moisture, no treated plates...
No treated nails
 
mark handler said:
Exterior walls are not interior, dry locations
And with that theory you would not need treated plates on exterior walls. They are intended to be dry. No moisture, no treated plates...
No treated nails
Click to expand...
I agree with that. If air can get to it there will be moisture. Why do we seal the plate to the concrete with caulk? It’s not to keep rain water from soaking floors.....it’s to prevent air transfer. With air comes moisture. The assembly of framing, lath and plaster has irregularities that thwart the seal. The weep screed sorta sits flat on the concrete. The lath paper is....well duh, it’s paper....or tyvek....or felt....tears, folds, staples and seams.....that’ll never leak.

Then there’s the plaster. Was the mixture correct? How about cracks? Look at a pink stucco building after it’s been raining for days. You can see the water line as it drains.

So the ICC says differently.....well that’s on them. I am stuck with what the ruling is and the tract I am currently involved with has one building with plain steel nails but the other six are being framed with galvanized nails. Henceforth it is whatever the builder chooses to use.
 
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ICE said:
Our Research Section found an ICC answer to the question. The ICC states that it is an interior, dry environment when constructed in compliance with the code. So plain carbon steel nails are allowed.

Click to expand...

I still wish you folks would upload the photos because links like this get lost when these photo sites change around or go out of business. We have a lot of photo links that are useless now.
 
So most are in agreement that an exterior wall cavity is not an interior dry location. But we have a big photo from ICC Q&A that contradicts what we believe.
I guess we agree to disagree
 
I will be talking with the guy that made this ruling. I have respect for ICC with limits. Little work done in the world of construction can be thought of as foolproof. The idea that the mud-sill is a dry environment based on the trades getting it right always .....well who other than ICC believes that? Their pie in the sky reasoning is not unique to a code making body. You should see some of the things that NRTLs endorse.

Any time I get a dictum I remind myself that Disneyland has alligators in the kids wading pond. A toddler was eaten in front of his father. A multinational corporation with 200,000 employees let an alligator rip a child from his father and eat it. 200,000 and I bet none would step foot in the wading pond yet nobody stopped to think about what they were doing.
 
jar546 said:
I still wish you folks would upload the photos because links like this get lost when these photo sites change around or go out of business. We have a lot of photo links that are useless now.
Click to expand...

2,668 pictures later. But not to worry, 99% of the pictures are in just two threads so if flicker goes down the impact to the forum won’t cause much harm.

I’ll take a look at uploading pictures here.
 
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"The idea that the mud-sill is a dry environment based on the trades getting it right always .....well who other than ICC believes that? " In other words, have them do something that the code does not require because they don't do something else that the code does require. I agree most don't get the water control layers right but I dislike the concept of accepting that and making them do ;something else.
 
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