Concrete slab floors are typically slower than elevated wood floors or basements1) – so there is are some economic reasons to prefer a flat house pad, as opposed to hillsides that may need pilings and/or retaining. But there is also the reality that cables have to be known and laid early, as any change means the floor has to be broken up and relaid. Ouch.
* deep foundations:
pile foundations: a type of deep friction or bearing based foundation. friction piles: transfer loads down via friction, using wood, steel or concrete columns.end bearing piles: transfer loads down, using wood, steel or concrete columns. combined friction/bearing piles: self-describing.micro-piles: used where driving is not feasible. A hole is bored, into which the micropile is grouted into place. screw/helical piles: sacrificial foundations made of steel that are screwed into the ground, without needing concrete, or causing much/any vibration to surrounding structures.batten/sheet piles: sheets of metal driven into the earthpier foundations: a type of deep bearing foundation, but shallower than piles, using large diameter columns to transfer large loads to firm strata below. Generally shallow (as oppossed to pile foundations). Used when:
* shallow foundations:
spread footing foundations: created under the frost level, under the perimeter walls and inner columns, with a wider bottom portion than the load-bearing foundation walls/columns they support (“spreading” the load over more area).mat-slab (or raft) foundations: Mat-slab foundations distribute heavy column and wall loads across the entire building area, to lower the contact pressure compared to conventional spread footings. Not common in residential, but appropriate if the soil is uniformly poor(excluding peat and organics).Slab on grade: a type of shallow foundation, where the concrete is directly poured onto graded soil, within a formed perimeter. Used where ground freezing and thawing is less of a concern and where there is no need for heat ducting underneath the floor. Although elevated slabs perform better, it's generally considered acceptable to use slab on grade over clay, and the best cost/benefit ratio for low-cost/tract housing, and generally avoided for better quality homes due to difficulties changing/adding/fixing things later.monolithic slab on grade: when the perimeter wall/column footings and slab are poured at the same time.floating slab on grade: when the perimeter wall/column footing are poured first, and the slab second.pad foundations:
* Insulated Concrete Forms (ICF)5): insulation + forming all in one. More expensive than traditional forming, but also provides insulation + vapour barrier + longer/stronger curing.
screed: the tool that is used to level and true a maerial like concrete.Screed coat: the material itself (eg: concrete) or a secondary thin, top layer of material (sand and cement, magnesite or calcium sulphate)) applied over underlying structural concrete or insulation, which has been flattened with a screed [tool], on top of which other finishing materials can be applied, or it can be left bare to achieve a raw effect.Gypcrete: a lightweight concrete for applying as a screed coat for leveling floors before carpet, etc. Lighter, but brittle. Note: not the same as light weight concrete.Light weight concrete: a lighter version off concrete (about 2/3rd the weight). If the ground is level, and the work is undertaken by professional builders, the most economical solution is a poured slab foundation. Otherwise, consider pole based construction so that the work can be undertaken by the same builder as being used for the structure.
If pouring a foundation, remember to consider: * Sandbox for draining tubs that can be post-finished (allows for location adjustment) 9) * Don't forget drainage of AC unit!10) * Kitchen:
* Bathroom
DIY'ers should consider the following:
Some common choices19) are:
