A construction company found formaldehyde leaking from floor joists supporting subfloors in about 2,000 homes they built.
|
|
And in homes with concrete subfloors, like many high-rise apartments, engineered flooring can be glued directly to the slab, whereas solid wood usually requires a plywood subfloor so it can be nailed in place.
|
|
The floor under the flooring is called the subfloor, which provides the support for the flooring. Special purpose subfloors like floating floors, raised floors or sprung floors may be laid upon another underlying subfloor which provides the structural strength. Subfloors that are below grade (underground) or ground level floors in buildings without basements typically have a concrete subfloor. Subfloors above grade (above ground) typically have a plywood subfloor.
|
|
Subfloors should be flat and it is not recommended to install on top of more than one layer of existing flooring. #Another installation method, secret nailing, offers similar benefits to the glue-down or fully bonded method for boards of at least 18mm. Thinner boards may require a glue-down or floating installation instead.
|
|
Varnished, painted or polished surfaces are not normally susceptible to attack but the female beetle may still lay her eggs in empty tunnels created by previous beetle occupants. Subfloors, joists and rafters are usually made of pine or other softwood and generally escape infestation. Imported tropical hardwoods may be heavily infested because of poor drying and storage practices before shipment.
|
|
The foam is produced by agitating a foaming agent with compressed air to make "aircrete" or "foamcrete". This material is fireproof, insect proof, and waterproof. It offers significant thermal and acoustic insulation and can be cut, carved, drilled and shaped with wood-working tools. This construction material can be used to make foundations, subfloors, building blocks, walls, domes, or even arches that can be reinforced with a construction fabric.
|
|
Portable subfloors are most often temporary floors which provide a solid surface over grass, sand, turf, or any other area where a more rigid surface is required. They can be installed quickly in any area by laying down panels, or rolling out and placing them in a cart for ease of storage. They are typically designed for outdoor use, and are extremely durable. A subfloor is typically about 1/2" to 2" thick.
|
|
The number of plies—which is always odd—depends on the thickness and grade of the sheet. Roofing can use the thinner plywood. Subfloors are at least thick, the thickness depending on the distance between floor joists. Plywood for flooring applications is often tongue and groove (T&G;); This prevents one board from moving up or down relative to its neighbor, providing a solid-feeling floor when the joints do not lie over joists.
|
|
This makes them economical and easy to install for temporary or low-usage purposes such as subfloors, crawlspaces, pathways, paving, and levelling surfaces. In general, they may be used for any application which requires a flat, clean surface. This includes use as a base or "sub-slab" for a larger structural slab. On uneven or steep surfaces, this preparatory measure is necessary to provide a flat surface on which to install rebar and waterproofing membranes.
|
|
From the different types of grout, a suitable one has to be chosen depending on the load. For example, a load of up to 7.5 tons can be expected for a garage access (2-component pavement joint mortar (traffic load)), whereas a cobbled garden path is only designed for a pedestrian load (1-component pavement joint mortar (pedestrian load)). Furthermore, various substructures determine whether the type of grout should be permanently permeable to water or waterproof for example by concrete subfloors.
|
|
Alveolinidae is a family of spheroidal to fusiform milioline foraminfera with multiple apertures and complex interiors in which chambers are subdivided into chamberlets and subfloors interconnected by passageways. As with all Miliolina, the test wall in alveolinids is porecelaneous and imperforate. In living individuals the pseudopodea emerge through the multiple apertures that line the apertural or leading face of the test. Alveolinids first appeared near the beginning of the Late Cretaceous, about 100 million years ago, some 150 million years after the superficially similar fusulinds became extinct at the end of the Permian.
|
|
Floors may be built on beams or joists or use structures like prefabricated hollow core slabs. The subfloor builds on those and attaches by various means particular to the support structure but the support and subfloor together always provides the strength of a floor one can sense underfoot. Nowadays, subfloors are generally made from at least two layers of moisture resistant ("AC" grade, one side finished and sanded flat) plywood or composite sheeting, jointly also termed Underlayments on floor joists of 2x8, 2x10, or 2x12's (dimensional lumber) spaced generally on centers, in the United States and Canada. Some flooring components used solely on concrete slabs consist of a dimpled rubberized or plastic layer much like bubble wrap that provide little tiny pillars for the sheet material above.
|
|
The physical archaeological evidence within this area may include built landforms, structural features, intact subfloors deposits, open deposits and scatters, ecological samples and individual artefacts which have potential to yield information relating to major historic themes including Agriculture, Housing, Land Tenure, Persons, Pastoralism and Cultural Sites. The Hambledon Cottage site contains a section of a sand body, thought to be deposited by the Parramatta River during periods of flood. From a geomorphic perspective, the sandbody has the potential to provide insight into patterns of river flow and flood events that could lead to a better understanding of the formation of the Parramatta River Valley. Excavation of sections of sand body on George Street, Parramatta have uncovered archaeological artefacts and deposits associated with Aboriginal people occupying the Parramatta area prior to the arrival of non-Aboriginal settlers.
|
|