If you want to buy a shed, a summer house or a garden shed in the UK, you will often have the choice to decide between a shed with a wooden floor and sheds offered without a floor. You could spare some money, if you decide for the option without floor. because the materials for the floor are among the more expensive ones. The bearers are often boiler-pressure impregnated by the manufacturers because they know, that these parts are usually only treated once and that is right before the erection of the garden shed because afterwards they are mostly unreachable for further treatment. This plus solid floor boards has its price.
So it’s your choice to decide, if and how much the wooden floor is worth the money. For your decision it is important to think about, what kind of use you have set aside for your garden shed. In the following articles we will look at different options for floors and how a floor adds to a garden shed according to its use.
You could prepare a mat foundation for your garden shed and put a floor-less summer house on it and use the foundation as a floor. You could lay paving slabs, use clay or simply use the normal ground. It would be trodden down in no time an become quite usable.
If you plan such a more basic approach, maybe for gardening or as a shelter against rain, then you still should take care, that the ground is well drained. Also you should prevent water from flowing into the shed in case of strong rains. Keeping the garden shed dry is the number one key to make it more durable and increase its lifespan.
The better option for such a floor would be to elevate the ground a bit or even better make a flat excavation with a slight incline to the side of the drainage and fill it with gravel. A floor made of a poured concrete slab or paving slabs also functions much better with a drainage, that could go all around the garden shed.
However, none of these options will give you the dryness, the comfort or the increase in durability of a well ventilated wooden floor above such a drained area. Even if you just plan to use the garden shed for gardening: the gardening tools will be much dryer in a garden shed with a wooden floor and that means less rust. Moreover with the evolution of families and personal interests such a garden shed quite often is rededicated to other uses over the long time of their existence, and for many of these is a floor the better option. We will mention a few specifics below.
Garden sheds can last for centuries, if they are kept dry. Wood is conserved by dryness much like foods like rice, spices or herbs. No organism can live without water. This is true for fungi as well as for insects. The well known „woodworm“, which as a matter of fact is not really a worm but the maggot of an insect with the Latin name of Anobium punctatum mostly only shows up in wooden buildings without heating, because otherwise it would just be too dry for him to be able to feed.
So to conclude this question: the moisture in a garden shed without a wooden floor will always be higher than in a shed with a well ventilated floor. So one of the most important functions of such a floor would be to expand the lifespan of the garden shed itself as well as the items stored in it, assuming that a high moisture is detrimental to many things especially those with iron parts.
So this is one of the most important reasons, why the costs and the efforts for a wooden floor in the garden shed are worthwhile. Moreover, whenever you would decide to use the shed for other purposes like for example a place to play for the kids, a garden office, or a place to stay in the garden during the rain, a wooden floor will largely enhance your personal comfort and the cleanliness for all users.
Except for very small garden sheds, like garden storage sheds or a small garden storage box or a tool shed, where you can find floors fixed to the walls, most larger garden sheds will have a construction of bearers resting on the ground on which the floor boards will be laid.
While building the underfloor, think about putting the bearers on higher points, be it point foundations or a stack of slabs in order to maintain a good underfloor ventilation, even if later some vegetation will surround your garden shed.
Some pieces of roofing paper below the points of contact between the bearers and the ground will help to keep the moisture away.
If you build your garden shed in DIY, think about using boilder-pressure impregnated beams. These can still use some more impregnation with special focus on the end-grained areas. Imagine that this will usually be your last opportunity for maintenance on those parts, which usually are out of reach once the garden shed is finished.
The same is true for the undersides of the floor boards. They also like a treatment before the construction phase.
We will approach different options of flooring for your garden shed in the second part, talk about their pros and cons and how to install them.