Indy Total Construction

A ground floor extension can be purpose-designed and built to suit your needs exactly, or it can be constructed from a number of standard prefabricated components purchased from an extension manufacturer. Which type you choose depends on what you will use it for. The former is ideal for bathrooms, kitchens, bedrooms, living rooms; the latter is more suited to laundry rooms, sun rooms, children’s play rooms, work-shops and so on, and includes simple metal-framed, full-glazed conservatories.

The most important parts of the structure of your new extension are the foundations, which support the walls and spread the load evenly across the ground. Consequently, their design is quite critical and should be carried out after consulting your local Building Code which will specify the type of foundations required for the job and the depth to which they must be dug, based on local ground conditions.

To be effective, foundations must lie on firm, stable sub-soil, and depending on the soil type this may mean digging to a depth of 3ft or more. The type of soil will also dictate the type of foundations needed, as will the method of construction of the extension.

For a purpose-built extension with brick or block walls, it is usual to lay concrete in a trench and build the walls on top but for lighter constructions, such as prefabricated buildings, a slab of concrete known as a “raft” is more common.

The most common form of foundation is the “strip” type. With these a layer of concrete at least 6in thick is spread along the bottom of the trench, leveled off, then the walls built on top. Normally, a width of 18in is quite adequate, but at depths below 3ft or on certain types of weak soil a width of 30in or more is preferable — often with steel reinforcement added.

The trench-fill foundation is filled with concrete to within 6in of the ground level and the walls begun.

The concrete for this type of foundation should be at least 20in deep and about 6in wider than the width of the wall. The sides of the trench must be vertical to prevent any possibility of the load above causing the foundations to topple.

The walls of a habitable extension to your house must be of cavity construction; that is comprising an outer leaf of bricks and an inner leaf of bricks or. more usually, concrete insulating blocks with a 2in Pit- gap in between giving a wall thickness of 1 lin, although the cavity may be 3in wide to accommodate polystyrene slab insulation and still leave an air gap.

Even if the main part of your house has solid outer walls, the Building Code specifies that your extension must be of cavity wall construction.

People walk, ride, and play on concrete and asphalt surfaces. Because the greatest use of these products is in floors, slabs, sidewalks, and streets, concrete and asphalt aren’t usually considered home repair problems. But almost every house has some cement in or under it. Concrete workers and finishers will always be in demand because cement is useful.

Mortar can be- mixed in a suitable container by hand. It contains Portland cement, sand and water and sometimes lime in certain proportions.

Depending on the job, you will need some of these tools for work with mortar or concrete. Always keep tools clean.

Add an aggregate to mortar and you have concrete. Concrete can be mixed in different proportions. One common mixture contains one part Portland cement, three parts sand, four parts aggregate and a little water.

Concrete can be mixed in a container such as a pail or a wheelbarrow or on a slab or piece of plywood. You can also use a small power mixer, but do not fill it more than half full or it will not mix properly. Never mix concrete on the ground. The slightest bit of mud weakens the concrete.

Cement means an adhesive that holds things together. Cement is a word that is often used in place of:

• Mortar or

• Concrete

Mortar is usually a mixture of sand and Portland cement used with or instead of lime for greater strength. It is used to cement bricks and tiles together. To prepare mortar, add the correct amount of water and mix. Mortar works best on a wet surface. Dry brick or block will absorb water from the mortar before it can set properly. Whenever possible, soak the block, brick, or wall to be patched before applying mortar.

When gravel, crushed stone, or some other aggregate is added to sand and Portland cement, it is called concrete. Concrete can be bought in different sized sacks. When mixed with water, one 80-pound sack of premix will make up an amount that will fill a section 4 feet by 4 feet by 1/2 inch. You can also purchase the sand, lime and aggregate separately and mix it by hand or with a power mixer 3). For big jobs it is easiest to order concrete by the truckload already made up and ready to pour.

A few basic tools are necessary for working with concrete or mortar. Be sure to clean all tools before the concrete hardens on them.