Build an additional living space with our 4 x 3m Self-Build Insulated Garden Room. Looking for extra space at home, need a cost effective solution? A Mercia Insulated Garden Room from allows every possibility. The modular design means you can place the doors and windows in a configuration to suit your needs. With 72mm thick double skinned walls, double glazed windows and fully insulated roof, floor and walls, this is the perfect space for all-year-round use. The flat roof creates a contemporary silhouette in your garden, whilst promoting excellent rain water run-off, helping keep your building dry for many years to come. The roof is covered with high-grade mineral felt. Mercia Insulated Garden Rooms are manufactured here in the UK, using sustainably sourced and regulated timber. The building comes with comprehensive instructions and a step-by-step video guide taking you through every part of the build. All fixtures and fittings are included as standard. We recommend a good understanding of DIY for the construction of this building. Please Note: A firm and level base is required for this building, either made of solid concrete or concrete slabs. It is recommended that the floor of this garden room is further covered by either carpet or laminate to reduce wear on the matchboards. Please Note: These Insulated Garden Rooms are NOT pre-treated or painted. In order to qualify for our 10 year anti-rot guarantee the building must be annually treated with a high quality spirit based wood preservative and a waterproof treatment.