Building a timber floor for a garden room is an important part of the construction process as it provides a solid, level base for the structure to sit on. A timber floor is also an excellent way to add insulation to the garden room and create a warm, comfortable space. Here is a detailed guide on how to build a timber floor for a garden room:
Step 1: Site Preparation
Before building the timber floor, you need to prepare the site by clearing the area and levelling the ground. Use a spirit level to check that the ground is level, and make any necessary adjustments by adding or removing soil.
Step 2: Create a Sub-Base
The next step is to create a sub-base for the timber floor. This involves laying a layer of compacted hardcore, such as crushed stone or gravel, to a depth of around 150mm. Then creating timber forms to pour a concrete foundation. Use a compactor to ensure that the sub-base is level and
Step 3: Install a Damp Proof Membrane
Once the sub-base is in place, install a damp proof membrane over the entire area. This will prevent moisture from seeping up into the timber and causing it to rot. Ensure that the membrane overlaps the edges of the sub-base by at least 150mm and fix it in place using a suitable adhesive.
Step 4: Install the Joists
The next step is to install the joists, which are the horizontal timbers that will support the floorboards. The size and spacing of the joists will depend on the size of the garden room and the weight it will support. As a general guide, the joists should be spaced at 400mm intervals for a 4m x 4m garden room.
Use treated timber for the joists to ensure that they are resistant to rot and insect damage. Cut the joists to length and fix them in place using joist hangers and coach bolts. Ensure that the joists are level and spaced evenly.
Step 5: Insulate Between the Joists
Once the joists are in place, you can add insulation between them. This will help to keep the garden room warm and prevent heat loss through the floor. Use an insulation material such as rigid foam board, and cut it to fit between the joists. Ensure that the insulation is flush with the top of the joists to create a level surface for the floorboards.
Step 6: Install the Floorboards
The final step is to install the floorboards. Use tongue and groove floorboards that are suitable for outdoor use and resistant to rot and moisture. Lay the first board along one edge of the garden room, ensuring that it is flush with the edge of the joist. Fix it in place using stainless steel screws or nails.
Continue laying the floorboards, ensuring that each board is level and flush with the previous one. Cut the final board to size and fix it in place. Leave a small gap around the edge of the floorboards to allow for expansion and contraction.
- Treated timber joists
- Tongue and groove floorboards
- Damp proof membrane
- Joist hangers
- Coach bolts
- Stainless steel screws or nails
- Spirit level
In conclusion, building a timber floor for a garden room requires careful planning and attention to detail. By following the steps outlined above, you can create a solid, level base for your garden room that will provide insulation and a comfortable living space.