WHAT ELSE DO I NEED TO THINK ABOUT?
The speed at which timber grows is important. The slower the better. Shire purchase timber only from forests in the northern hemisphere where conditions are extremely cold and trees grow very slowly. Timber should be ‘Seasoned’ – why? Timber for garden buildings should be seasoned. This means that the timber is kiln dried to reduce the moisture content of the timber. This also kills any insect infestation. For buildings timber should be dried so that the moisture content is below 20%. The more moisture left in the building the more movement will occur when the timber dries out. If buildings are to go outside timber will gain and loose moisture, timber for inside usage won’t. Timber for furniture is dried to 12%. All timber purchased by Shire is kiln dried to 18%. Some Overlap is machined from home grown timber which isn’t kiln dried at all. Home grown Overlap was traditionally, as still is, used for low quality fencing. It is prone to movement and because it isn’t kiln dried any insects present in the tree may still be present in the boarding. Shire Overlap is produced from kiln dried timber, the same timber used to produce tongue and groove timber.
Knots are where a branch used to be, and to state the obvious, all trees have branches. If a knot is a live knot there will be a knotty part on the timber, if the branch was dead when the tree was felled the knot has died there will be a hole where the dead knot has fallen out.
All timber is graded. There are 5 grades, 5th being the worst and 1st being the best. Grading will sort out the quality of the timber looking at the amount of splits and the amount and location of dead knots/holes. Shire buy only 1st and 2nd graded timber.
Timber is always sold in sizes of timber before machining this is known as the nominal measurement. The measurement after planning is the actual measurement and this is the size you should be concerned with as this is what you will get.
There are different types of timber that can be used as cladding material.
This is the most economical timber choice, but be careful. Home grown timber will expand and shrink much more than kiln dried timber, seasoned timber. With Home Grown there is very little, if any, quality control. This type of timber is more suited to fencing. In Shire products we use the same raw material and produce overlap as we do to produce tongue and groove material. Not everyone else does.
TONGUE AND GROOVE
Shiplap and Matching are patterns of tongue and groove timber. Tongue and groove timber allows for some movement of the boarding without leaving gaps. Shiplap is traditionally used for the walls, whereas Matching is used for the roof and floor.
For constructed panels, the thicker the better. The more framework the better. Thin framework and little of it will cause the building to be flimsy.
ROOFS AND FLOORS
Many buildings have Oriented Strand Board (OSB) roofs and floors. Solid timber floors are more expensive. There is nothing wrong with OSB, providing buildings are stored under cover whilst waiting for despatch.
Shire are the only manufacturer who store all stock prior to despatch inside, all the time. The floor – is it included in the price of the building or an optional extra at extra cost? All Shire buildings have floors, except garages.
Your timber building will need to be treated prior to assembly (except log cabins which should be treated following assembly) and at least annually thereafter, but as instructed by the manufacturer of the treatment used. We would recommend that your building is treated prior to assembly and again within 3 months of assembly.
Almost all buildings need to be treated to protect the timber from the elements, mould and insects. This can either be a solution applied to the surface of the timber or the timber can be pressure treated.
Treatment applied to the surface of the timber will need to be retreated annually to protect the timber. Pressure treated timber doesn’t need to be retreated to protect the timber but you may decide to treat anyway for aesthetic reasons as pressure treated timber will turn grey over time.
Shire recommend that floor joists are not in contact with the ground. This can be achieved by using a damp proof layer between the base and the joist or alternatively construct a base from pressure treated timbers so that the floor of the building lays across.
Care should be taken to ensure floor joists are treated properly.
Shire do not recommend the use of Pressure Treated tongue & groove cladding as this has a tendency of excessive shrinkage as the impregnated timbers dry. Shire Log Cabins are not treated as treatment prior to construction causes the timber to expand resulting in the boarding not fitting together properly. The floor joists are, however, pressure treated.
Most buildings will need to be treated prior to construction in a good quality preservative. Shire also offer a ‘top coat’ option to save you the job (not available for Log Cabins). On top of the base coat we apply a layer of good quality wood preservative in honey brown.
WHAT TO BUILD ON
The base onto which the building is to be placed must be absolutely firm and level. If it isn’t the doors and windows will warp and not open or close as they should. Also an uneven or base that is not level will put strain on panels that could lead to long term damage.
There are several options you may consider to create a firm, level base – concrete or paving slabs. Pressure treated bearers may be laid on top of the constructed base to lift the building away from surface water, although pressure treated bearers are not suitable for large buildings.
Alternatively, adjustable bases are available for some building sizes which level out a slight slope and keep the floor joists away from standing water. This method is suitable for use on firm soil or lawns.
Whichever method you decide upon you should leave a minimum of 18” or 450 mm all around for access whilst assembly the building and maintenance work. You should also remove any overhead obstructions that could interfere with the assembly of the building or damage it during use. If using bearers, ensure that they run in the opposite direction to the floor joists in the building.
BUILDING YOUR BUILDING
If you decide to build your building yourself you will need a helper. Depending on the size of the building and your own experience will dictate how long it will take. As a rough guide, a small shed should take around half a day whereas a log cabin with felt tiles may take 2 days.
You will need various tools – as a minimum; a hammer, screwdriver (powered is best), drill and bits, sharp knife, saw, tape measure, step ladder, spirit level; and to protect yourself a pair of non-slip gloves and a some work boots, preferably with steel toecaps and steel sole. If you decide to employ a builder, shop around, prices can vary enormously.
Alternatively, Shire offers an assembly service. Delivery and assembly will take place at the same time.