Can I insulate my log cabin?Updated 13 days ago

Our log cabins naturally provide excellent insulation thanks to the 44mm or 28mm timber logs. Most customers find they don’t need additional insulation—especially as a small heater can quickly warm up the space due to the timber's natural heat retention.

However, if you'd like to enhance the cabin's energy efficiency, particularly for year-round use or in colder climates, you can insulate key areas. Typically, the roof and floor are the most beneficial places to insulate. Some customers also choose to insulate the walls, but it's important to account for the natural movement of timber logs when doing so.

Where Should You Insulate?

1. Roof
 The roof is the main area where heat escapes, so insulating it can have the biggest impact.

• Useful Tip: Use 25mm PIR board insulation (e.g., Kingspan or Celotex) over the roof boards. Tape the joints with foil tape for a sealed thermal barrier.
• Finish Tip: Cover the insulation with 12mm structural plywood or OSB board, then add the EPDM rubber roof for a durable and watertight finish.

2. Floor
 Insulating the floor prevents heat from escaping downward and blocks cold drafts from underneath.

• Useful Tip: Fit 25mm PIR board insulation snugly between the floor joists. Use expanding foam for any gaps to ensure a tight fit.
• Membrane Tip: Consider adding a Damp Proof Membrane (DPM) beneath the base or over the foundation to protect against moisture ingress, which can damage the timber or insulation.
• Reinforcement Tip: Double up the floor battens at stress points (e.g., 2400mm intervals) to support heavy furniture or equipment.

3. Walls (Optional)
 Some people choose to insulate the walls for maximum thermal efficiency, but it’s less common. If you do, you must consider the natural expansion and contraction of the timber logs.

• Floating Wall Technique: Build an internal stud frame for insulation and cladding that doesn’t attach directly to the log walls, allowing them to move naturally.
• Insulation Choice: Use insulated plasterboard (e.g., Kingspan Kooltherm K118 or Celotex PL4025) for a combined insulation and smooth interior finish.
• Preparation Tip: Apply Zinsser BIN to visible knots in the timber to seal them and prevent resin bleed before adding insulation or cladding.

Additional Considerations

• Ventilation: Proper airflow is crucial to prevent condensation and damp. Install vents (e.g., slider vents inside and louvered vents with flyscreen outside) to ensure good air circulation.
• Sealing Gaps: Use flexible clear exterior sealant to fill gaps around doors, windows, and bargeboards for added thermal efficiency and weatherproofing.
• Wiring Considerations: Plan for any electrics early, leaving gaps in floor or wall insulation for cables and creating vertical loops for sockets where required.
• Durability: Treat the timber base and floor with Protek Wood Preserver Plus to protect against rot and decay in high-moisture environments.

Do You Need to Insulate?

For most customers, additional insulation isn’t necessary. The natural insulating properties of timber logs, combined with a small heater, are sufficient to create a cozy and warm cabin. If you do choose to insulate, focusing on the roof and floor will give you the most benefit. Insulating the walls is optional and should only be done with consideration for timber movement.

By tailoring your approach to your specific needs, you can enjoy a cabin that’s comfortable, efficient, and built to last.

*Please note the above guidance is simply a suggestion and you should always consult with a professional when looking to amend your log cabin. Check out full Guarantee terms here.