General notes for pressure-treated wood 2

[skeletron]

Is anyone willing to share how they call up pressure-treated wood? Do you just point to a standard, or do you indicate acceptable PT methods? I'm noticing some discrepancy between some of the info I have on file.

My span tables indicate not incised vs. non-incised. Some old drawings I have say to pressure-treat but without using ACQ, CA-B, SBX. Another set just refers to a standard.

 

[dik]

I meant to reply...

PRESERVATIVE TREATMENT

ALL LUMBER IN CONTACT WITH CONCRETE SHALL BE PWF TREATED

TYPICAL LEVELS OF PRESERVATIVE SHALL BE:
-[0.25PCF | 4.0KG/CU.M] FOR ABOVE GRADE AND NON-STRUCTURAL USE
-[0.40PCF | 6.4KG/CU.M] FOR ABOVE GRADE AND STRUCTURAL USE OR IN CONTACT WITH GRADE AND NON-STRUCTURAL USE
-[0.60PCF | 9.6KG/CU.M] FOR BOTH IN CONTACT WITH GRADE AND STRUCTURAL USE


PRESERVED WOOD FOUNDATIONS

ALL WORK TO CONFORM TO THE MBC, [NBCC | MBC |SBC], CSA STDS S406 AND 086 AND CWC WOOD TEXT SERIES 3 "PERMANENT WOOD FOUNDATIONS"

MAX BACKFILL HEIGHT NOT TO EXCEED REQUIREMENTS OF CSA S406. DETAILS TO CONFORM TO THE CONSTRUCTION GUIDE FOR WOOD FOUNDATIIONS PWF-1, REV EDITION

ALL LUMBER AND PLY USED FOR PWF SHALL BE BEAR A CERTIFICATION STAMP THAT IT HAS BEEN TREATED TO CSA STDS O121, O322, O80.15 AND O151. PWF PLY SHALL BE [5/8 | 15] MIN, INSTALLED WITH GRAIN HOR U/N. ALL JOINTS SHALL BE BACKED WITH STUDS OR SOLID BLOCKING HAVING THE SAME NOMINAL SIZE. ALL PLY JOINTS AND THE BOT PL TO THE FOOTING SHALL BE CAULKED WITH BUTYL SEALANT TO CAN/CGSB 19-GP-13M OR CAN/CGSB 19-GP-14M

THE FOLLOWING INFORMATION SHALL BE SHOWN ON THE STAMP:
-IDENTIFICATION OF CERTIFYING AGENCY
-GRADE MARK PWF AND/OR FTB
-DESIGNATION O322
-PRESERVATIVE TREATMENT TO BE CCA
-IDENTIFICATION OF TREATMENT PLANT AND YEAR OF TREATMENT

ALL PWF STUDS SHALL BE SPECIES 1, GRADE 2 OR BETTER U/N. SIZE AND SPACING AS NOTED ON THE DRAWINGS. PLY TO BE UNSANDED, EXTERIOR, 4 PLIES MIN TO CSA-O121. LENGTH OF STUD TO BE [8FT | 2.4M] MAX. HEIGHT OF BACKFILL TO BE [6FT | 1.8M] MAX

FIELD CUT LUMBER MEMBERS SHALL BE TREATED WITH SUITABLE PRESERVATIVE PROVIDED BY THE LUMBER SUPPLIER. EXTERIOR WALL PL LOCATED [8 | 200] MIN ABOVE GRADE AND FLOORS LOCATED [12 | 300] MIN ABOVE THE GRANULAR DRAINAGE LAYER NEED NOT BE PRESERVATIVE TREATED

CUT EDGES OF ALL PWF LUMBER TO BE TREATED WITH TWO APPLICATIONS OF A 2% SOLUTION OF COPPER NAPATHANE TO CSA O80.201

THE HEIGHT OF FINISHED GRADE SHALL BE THE SAME FOR ALL PWF WALLS U/N

THE TOP OF THE DRAWING SHALL BE CONSTRUCTION NORTH U/N. NAIL SPACING FOR ALL NORTH AND SOUTH FACING WALLS SHALL BE [8 | 200] O/C WITH PANEL EDGES NAILED AT [4 | 100] O/C. NAIL SPACING FOR ALL EAST AND WEST FACING WALLS SHALL BE [8 | 200] O/C WITH PANEL EDGES NAILED AT [4 | 100] O/C

NAIL SPACING FOR ALL WALLS SHALL BE [8 | 200] O/C WITH PANEL EDGES NAILED AT [4 | 100] O/C

NAILS SHALL CONFORM TO ASTM F1667 AND SHALL BE HDG TO G185. NAILS SHALL BE HAND NAILED ONLY

THE EXTERIOR PEVB SHALL CONFORM TO CSA 2.51.34 AND SHALL HAVE A 6 MIL MIN THICKNESS. LAP ALL JOINTS [24 | 600] MIN AND SEAL WITH A DOUBLE BEAD OF BUTYL SEALANT. THE TOP JOINT SHALL HAVE A [6 | 150] FOLD AND SHALL BE SECURED AND SEALED TO THE PWF PLY WITH A CONT BEAD OF BUTYL SEALANT AND SHALL BE COVERED WITH [1/2X12 | 13x300] WIDE PWF PLY. TOP OF COVER STRIP TO BE [3 | 75] MIN AND [6 | 150] MAX ABOVE FINAL GRADE. THE PEVB SHALL EXTEND CONT [2 | 50] MIN ABOVE FINAL GRADE ([1 | 25] BELOW THE TOP OF THE COVER STRIP) TO [2 | 50] DOWN THE THE EXTERIOR FACE OF THE CONC FOOTING. SECURE EXTERIOR PEVB TO PWF PLY BY EMBEDDING IN VERT BEADS OF BUTYL CAULKING @ [48 | 1200] MAX O/C. DO NOT SEAL ALONG BASE OF FOUND WALL WITH SEALANT. LAP PEVB [6FT | 1.8M] MIN AT END OF THE ROLL AND SEALED VERTICALLY WITH BUTYL CAULKING. PEVB SHALL BE PROTECTED DURING BACKFILL BY MIRRDRAIN BY MIRAFI OR BY AN APPROPRIATE INSULATION MEMBRANE

ALL BACKFILL AND DRAINAGE AGGREGATE SHALL BE [1 | 1-1/2] [25 | 40]CLEAN CRUSHED STONE U/N

COVER AGG INSIDE FOUND WITH 6 MIL PEVB OVER ENTIRE EXCAVATION. INSTALL [2-1/2 | 65]%%C PIPES THROUGH CONC FOOTING @ [48 | 1200] MAX O/C. PROVIDE [2 | 50] MIN SAND OR CONC BALLAST OR AS SPEC

NO DEVIATION FROM THE STRUCTURAL AND MOISTURE BARRIER DETAILS SHALL BE MADE UNLESS WRITTEN APPROVAL IS OBTAINED FROM THE [OWNER | CONSULTANT | ENGINEER]

FLOOR JOISTS AND PWF WALL STUDS SHALL BE ALIGNED; WHERE PWF STUD WALL IS PERP TO FLOOR JOISTS, PROVIDE SOLID BLOCKING BTN JOISTS TO MATCH PWF STUD SPACING. FRAMING ANCHORS AND STRAPS SHALL BE A 20 GA MIN TO ASTM A446. HDG TO G185 MIN

SECURE PWF WALL BOT PLATE STOP TO FOOTING WITH 1/2" %%C X 12" HDG BOLTS C/W HDG WASHERS AND NUTS @ 32" MAX O/C. APPLY PWF PRESERVATIVE IN ACCORDANCE WITH MANUFACTURER'S PRINTED INSTRUCTIONS AT ALL BOLT HOLES IN BOT PL STOP

DO NOT DRILL HOLES THROUGH PWF WALL STUDS

BACKFILL SHALL BE HAND TAMPED IN [6 | 150] MAX LIFTS AND SHALL EXTEND TO WITHIN [24 | 600] OF FINISHED GRADE U/N. REMAINING BACKFILL TO BE [6 | 150] MIN IMPERVIOUS CLAY WITH [6 | 150] MIN TOPSOIL. DRAINAGE AGG SHALL EXTEND 12" MIN FROM FOOTING . SLOPE FINISHED GRADE 1/12 MIN AWAY FROM DWELLING

DO NOT PERMIT MOTORIZED EQUIPMENT WITHIN [8FT | 2.4M] OF THE FOUNDATION WALL. DO NOT BACKFILL WALLS UNTIL ALL ELEMENTS NECESSARY FOR LATERAL BRACING ARE SECURELY IN PLACE. FOUNDATION SOIL & CONC SHALL BE PROTECTED FROM FREEZING. PROVIDE TEMPORARY HEAT WHEN TEMPERATURE IS BELOW -10C UNTIL WALL IS BACKFILLED AND BUILDING HEATING IS IN OPERATION

CARE SHALL BE TAKEN AT ALL TIMES TO PREVENT DAMAGE TO MATERIAL THROUGH CARELESS HANDLING AND OVERLOADING DURING UNLOADING, STORING AND ERECTION


Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[skeletron]

Thanks Dik. I was hoping you would reply.
So, you don't necessarily indicate which preservative treatments are acceptable? Just the levels of preservative that are typical and standard handling requirements. Interesting.

 

[Canuck65]

I would recommend getting a copy of the CSA-O80.1 standard. It has lots of information related to pressure treated wood.

The CSA O80.1 Standard specifies four Use Categories (UC) for treated wood used in construction:

UC1 covers treated wood used in dry interior construction;
UC2 covers treated wood and wood-based materials used in dry interior construction that are not in contact with the ground but can be exposed to dampness;
UC3 covers treated wood used in exterior construction that is not in ground contact;
UC3.1 covers exterior, above ground construction with coated wood products and rapid run off of water;
UC3.2 covers exterior, above ground construction with uncoated wood products or poor run off of water;
UC4 covers treated wood used in exterior construction that is in ground or freshwater contact;
UC4.1 covers non-critical components;
UC4.2 covers critical structural components or components that are difficult to replace;
UC5A covers treated wood used in Coastal waters including; brackish water, salt water and adjacent mud zone.
This CSA O80 Series of standards consists of five standards, as follows:

CSA O80.0 General requirements for wood preservation; specifies requirements and provides information applicable to the entire series of standards.
CSA O80.1 Specification of treated wood; is intended to help specifiers and users of treated wood products identify appropriate requirements for preservatives for various wood products and end use environments.
CSA O80.2 Processing and treatment; specifies minimum requirements and process limitations for treating wood products.
CSA O80.3 Preservative formulations; specifies requirements for preservatives not referenced elsewhere.
CSA O80.4 has been withdrawn.

Also you can see some less technical information on the MicroPro Sienna website.

https://microprosienna.com/wp-content/uploads/2017/09/MicroProSienna-Technical-Data.pdf

Typically we would specify the UC (User Category) from the standard and make sure that the UC category is suitable for the application. We also will talk about the type of fasteners permitted with the specific type of preservative treatment.

 

[phamENG]

Here in the states, we have the American Wood Protection Association, AWPA. They publish the U1, which is a use classification system. They break things down both by commodity type, usage within a structure, or more generic exposure conditions, and assign a category. Then they go into what is acceptable for certain categories. I usually just require the materials to bear an AWPA UC stamp for the appropriate usage - if I think it needs something a little more I'll define the use category I think it needs. I don't typically get all the way into chemicals or even how much of the chemicals. I might restrict the use of something if the client requests it, but that only happened once for a waterfront job in an environmentally sensitive area.

It looks like it's about the same as the CSA 080.1.

 

[NorthCivil]

All fasteners and connections need be stainless steel? as the chemicals in treated wood will corrode your steel fasteners rapidly?

or have the chemicals used in treatment process changed?

 

[dik]

I normally spec PWF for nearly all preservative treated lumber... I've seen lesser stuff 'disappear', and the PWF sticker covers just about anything. Fasteners are the real kicker and stainless is the best, but pricey. I've had excellent results from polymer coated HDG fasteners... cheaper than stainless and very good. For mild environments HDG are the minimum... and make sure it's not electroplated zinc... that keeps rust away while it's still in the packaging. I heard that people buy it because it looks shiny. The CSA specs by that other Canuck are good reference (who gets a star for his excellent reference)... also the attached links... and I've got a bunch of *.pdf files tucked away with added info, mostly on ACQ, CA and CCA... ACQ and CA lack corrosion-inhibiting chromium and arsenic, and have a much higher copper concentration than CCA and tend to be more corrosive. I don't do many houses, but I did a bunch of teacherages with preserved wood foundations about 40 years back up in northern Canada... use a treatment called Boledin Boliden, scandanavian at the time... and extremely good.

https://www.internationaltimber.com/resources/what-are-the-best-types-of-wood-preservatives/

https://www.jlconline.com/deck-builder/fighting-fastener-corrosion_o

This is from about 50 years back... and gives an idea of how preservative treatment has changed (historic value)... "Standard wood preservatives used in water solution include chromated zinc chloride, copperized chromated zinc chloride, Tanalith (Wolman salts), acid copper chromate (Celcure), ammoniacal copper arsenite (Chemonite), chromated zinc arsenate (Boliden salt), chromated copper arsenate (Greensalt or Erdalith), and Osmosar (Osmosalts). Recommended retentions of these chemicals vary from 0.3 pound to 1.00 pound per cubic foot for wood used on farms. 2 These preservatives are employed principally in the commercial treatment of wood for uses where it will not be in contact with the ground or water, a"

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik