in addition to the consideration for an above-ground wall what additional factors must you consider for PWF walls?
dealing with decay, moisture, and lateral forces applied by the soil
what should you look for on the material you buy to use for a permanent wood foundation?
should always bear a certification mark it designates the use of the material and is permanently stamped into the lumber
besides being east to insulate an to finish the inside, name another benefit of choosing a pwf permanent wood foundation system.
the carpenter can frame it reducing amount of trades needed
what must be done to the excavation for a PWF to allow moisture to travel away from the foundation?
usually made deeper than required and replaced with a granular material that will allow unrestricted travel of moisture which allows it to quickly flow away from the foundation, usually slopes to the centre with a sump pump
what are 3 types of footings acceptable for a PWF system?
1. treated wood
2. continuous concrete strip on granular fill
3. continuous concrete strip on undisturbed soil
what must be added to the footing for a PWF basement if it is placed on undisturbed soil?
the footings must have pipes installed to allow passage of water to the sump pump
what must be done to the cut ends of PWF material?
the cut end must be treated with copper chrome arsenate cca
list the safety guidelines to follow when cutting and treating PWF material.
wear a dust mask and rubber gloves
what are the common sizes of lumber used for framing PWF walls?
2 by 6 and 2 by 8
if the fasteners and connectors for PWFs must be corrosion resistant, what types should be used?
hot tipped galvanized, stainless steel, and connecting hardware must be galvanized
how do you frame an opening in a pwf wall to resist the soil pressure placed on it?
by installing joist hangers and framing connectors around the opening
large openings like stairwells near the PWF wall may need special attention. what might be required?
always check the main floor plan for stairway openings near the outside wall. the plan details may require additional material in the top to the PWF walls to from a lateral beam across the opening
what are 3 reasons for adding blocking in a PWF wall?
1. backing for plywood edges
2. strapping at inside corners
3. baseboard attachment
are nails or concrete pins through the bottom plate of the PWF wall into the footing all that is required to hold the bottom of the wall for backfilling?
you cannot rely on this to hold the bottom of the wall for backfilling, the basement floor must be in place to hold the bottom of the wall before backfilling
what are 3 types of basement floor systems commonly used for PWF?
2.wood on sleepers
3.wood suspended floor
why must the plywood be installed on the floor before backfilling?
plays an important part in transfering the lateral loads throughout the floor and must be installed before the foundation is backfilled
what must be closely fallowed if an engineered joist system for the floors is used?
follow the installation details provided it is critical when using this type of floor
what 2 things help prevent the infiltration of moisture past the plywood of a PWF wall?
1. use caulking between sheeting joints
2. apply a sound moisture barrier to foundation below grade
what are the 3 common types of insulated concrete forms (ICF)?
block, plank, or panel
what should you use to trim or cut ICF forms to size?
hand saw, folding trim saw, or a portable table saw
what must be fallowed in every detail to prevent blowouts and form failures in ICF's?
the installation guide
what allowance must be made at the bottom of door bucks to allow for settlement of the ICF's?
the sides should be cut 1/2" short so that if the forms settle it wont put extra stress on it and push it out of place
how should you hold bucks in place when using insulated concrete forms?
by using 3" drywall screws with large plastic washers
explain why the top row of forms is wired or taped to the second row in the ICF system.
the top row takes a lot of abuse. attaching the wire/tape prevents them from being knocked loose or floating when the concrete is poured
what should be done to the end of the delivery hose when using a concrete pumper truck to place concrete into ICF's
install 2 90 deg. elbows and reduce nozzle at end to 3" both reduce the velocity it is also recommended that the hose be allowed to lay flat on top of the forms so the concrete just drops in as apposed to putting the hose down the form to damage it
explain 2 methods of repairing a blowout while placing concrete in insulated concrete forms.
1. use a threaded rod and 2 2 by 4 s push the rod threw the form and us nuts and washers on the lumber
2. screw ply wood or lumber over the problem forms
how should you attach siding to ICF's?
by using screws to attach it to the embedded plastic strips in block style or by adding metal strips screwed to the tie pads
why is metric layout easier to deal with when building a concrete block foundation?
concrete blocks are only available in metric sizes
how can proper placement of the rebar dowels in the footings when preparing for a block foundation make assembly easier?
if placed properly they will be in the cutouts of the blocks and won't interfere whith assembly
e the measurements for openings on a plan for masonry done different that on regular plans?
its measured to the edges rather that to the centre of the opening
why is it important to allow some flexibility in the positioning of openings when using a block foundation?
it may be shifted slightly to fit the modular sizes of the blocks and reduce cutting
explain why the sides of bucks for concrete block walls are cut slightly shorter than required?
it should be short with shims installed so when you need to move them you just remove the shims and done
why is the parging (thin coat of mortar) on the outside of the concrete block foundation coved?
to fill the corner and direct water away from the base of the wall
explain what a fire cut is and why it is used on floor joists going into a block wall.
a sloped cut on the end of the joist so if a fire occurs it can easily fall out without lifting the wall above it
how long does it typically take a factory trained crew to install a precast concrete foundation?