1. Final Project - Materials - Moisture Protection and Thermal Insulation Flashcards
Admixtures
mixtures added to conrete mix to make it water repellent
- materials such as salts of fatty acids, mineral oil, and powdered iron
- reduce strength of concrete, but make it less permeable to water
bituminous coatings
asphalt or coal-tar pitch materials applied to the exterior side of the foundation wall
-brushed or sprayed on, not in cold
cementitous coatings
- portland cement mortar troweled on masonry or concrete foundation walls
- mortar coatings are used on rough surfaces to make them smooth
membrane
- built up layers of hot or cold applied asphalt felts or membranes of butyl, polyvinyl chloride, and other synthetic materials
- usually used for waterproofing walls subject to hydrostatic pressure
plastics
made of silicone and polyurethane coatings
-reserved for above grade damping
dampproofing
control of moisture that is not under hydrostatic pressure
waterproofing
control of moisture under hydrostatic pressure
bentonite panels
flat packages of bentonite panels inside kraft paper packages
- placed under slabs and against walls
- after backfilling the clay expands in the presence of moisture to form a waterproof barrier
When describing size, estimating, and ordering materials, roofing area area is referred to in …
… squares. A square is equal to 100 square feet
Shingle Exposure
shingles are laid so that only a certain portion of each shingle is visible: this is caled exposure
- this dimension varies with the pitch of the roof
- 30 lbm asphalt felt is used as an underlayment
Slate tile
- made by splitting quarried slate into rectangular pieces from 6 in to 14 in wide and from 16 in to 24 in long
- about 1/4” thick
- laid over 30 lbs asphalt roofing felt
- very expensive but very durble and fire resitant ; can last over 100 years
Clay tile
similar to slate tile in roof buildup
-also expensive bu durable and fire resistant
concrete tile roofing
less expensive than clay tile
also very durable and fire resistant
metal roofing
- materials include copper, galvinazed iron, aluminum, and terneplatem stainless steel
- durable, attractive, can conform to a wide varaity of roof shapes
- high cost and difficult to install properly due to a high coefficient of expansion
- joints must be designed to account for expansion and contraction
- installed over asphalt roofing felt laid on top of wood or nailable concrete decking; exception to underlayment is for terne or tin roofs, which require a rosin-sized paper because asphalt can react with the tin
terneplate
steel sheet coated with lead and tin
minimum slope for metal roof
3:12
Name roof components
Horizontally applied board sidings
• In Europe, siding is nailed to vertical wood spacers (1x3’s) that are aligned over
the studs…called a rainscreen and creates a pressure equalization chamber
behind the siding that acts to prevent water penetration in a wind drive rain
- In the US, boards are nailed tightly over the wall sheathing and housewrap
- Allows for installation over insulating sheathing materials without requiring a nail based sheathing
preformed roof panels
- shaped pieces of metal or assemblies of metal with insulation between that are self supporting at intermediate supports
- roof panels span purlins, and wall panels span horizontal girts
- corrugated or fluted sheets
- made from aluminum, galvanized steel, and porcelain enamel steel
- most economical when used on large, flat, unbroken expanses of walls and roofs
Membrane roofing
- includes materials applied in thin sheets to nearly flat roofs
- includes liquid applied products that can be applied to any roof slope
built up bituminous roofing
- consists of several overlapping layers of bituminous saturated roofing felts cemented together with roofing cement
- bituminous material can be either asphalt or coal pitch tar
built up roof can be installed over nailable and non-nailable decks
for nailable deck: a base sheet of unsaturated felt is nailed to the deck and covered with a coating of roofing cement
on non-nailable decks: base sheet is omitted and a base coat is applied
- three, four, or five layers of sturated roofing felts are then laid on top of each other, each layer bedded in roofing cement so that felt does not touch felt
- a final coating of bituninous coating is placeed over entire roof and covered with gravel
- gravel protects the roof from sunlight and other effects of weathering
inverted membrane roof
- built up roof is placed on the structural decking and rigid, closed cell insulation is placed over the roof rather than under it
- insulation is held down with gravel ballast
- purpose of this type of construction is to protect the membrane from the normal deleterious effects of expansion and contraction, drying ultraviolet rays, and foot traffic than can cause leaks
cricket
saddle shaped projection on a sloping roof used to divert water around an obstacle
scuppers
- also called overflow drains
- built through parapet, positioned with their low edge slightly above the top of the roof to provide a second means of drainage should the primary drains become clogged
single ply roofing
-a single membrane layer of various types of materials
EPDM
ethylene propylene diene monomer
- only available in black
- must be sealed with adhesive or pressure sensitive tape
CSPE
chlorosulfonated polyethylene
- also known as Hypalon
- available in black and white
PVC
polyvinyl chloride
- relatively inexpensive
- seams are heat welded
- available in white
TPO
thermoplastic polyolefin
which can be recycled and reused for roofing: thermoplastics or thermoset plastics
thermoplastics only
Liquid applied roofing
- includes butyl, neoprene, hypalon
- also used for below grade waterproofing on foundation walls, tanks, and pools
- well suited for complex roofs such as thin-shell conrete domes
roof expansion joints
- required in buildings to allow for roof movement caused by temperature changes in materials and differential movement between builing sections
- located evey 100 ft in long buildings
- located at the junciotns of T, L, and U shaped buildings
A building with a basement is being design in a wet climate. Which of the following water control materials/method would an architect recommend?
cementitious coatings
geotextiles
french drains
sloping soils away from the building
geotextiles
french drains
sloping soils away from the building
cementitious coatings are only used for dampproofing
geotextiles
Geotextiles are permeable fabrics which, when used in association with soil, have the ability to separate, filter, reinforce, protect, or drain.
Typically made from polypropylene or polyester.
the minimum suggested pitch for a normal slope asphalt composition shingle roof is
4:12
in order for a asphalt or composition shingle roof to have a 2:12 slope, what must me built into the roofing
a double layer of roofing felt is required
-most manufactureres don’t recommend this slope
What is used to keep water from penetrating an expansion joint at the intersection of a roof and wall?
counterflashing