Internal Wall Insulation - Application – Celenit Wood Wool Boards & Thermafleece Sheeps Wool Application Guide
Bethany Evans Posted this on 29 May 2024
Preparation
- IMPORTANT: Protect your eyes with safety glasses (ones with sides) and keep eyewash close to hand!
- Tip: Lime is caustic and can seriously damage eyes. Goggles are essential at all stages.
- IMPORTANT: Wear gloves and cover skin. Lime burns are gradual (i.e. you don’t feel them at the time) but can be very serious so PPE is essential.
- Tip: Thin, disposable gloves are easiest to work with.
- Remove any loose any crumbly material. Particularly any cementitious or gypsum-based materials.
Application
- Apply flexible insulation between joists (Thermafleece/Flex 50)
- Tip: Ensure a snug fit, avoid squashing.
- If required install variable vapour check beneath rafters
- Tip: Use Tescon Vana tape to seal edges
- Apply Celenit Wood Wool to joists, fix with washers and screws. (8 per m²)
- Tip: Work from the base upwards, joints must be staggered.
- Apply first coat of Tŷ-Mawr Lime Hemp Plaster.
- Trowel mesh into face of plaster.
- On the same day apply further Tŷ-Mawr Lime Hemp Plaster to cover mesh, overall thickness should be approx 9mm. Once “stiffened up” brush surface to provide key for final coat.
- Tip: Plaster should be too firm to dent with a knuckle but soft enough to mark with a finger nail.
Finishing Options
- Internal Finish Plaster - 3mm
- 50/50 Mix of Fine Hemp and Super Fine Internal Finish plaster - 3mm - 6mm
- Fine Hemp Plaster - 6mm
- Apply final coat as per Finishing Options. Finish Plaster and 50/50 mix should be applied in two passes. Tŷ-Mawr Lime Hemp Plaster in a single pass. Trowel/ sponge as required.
- Tip: Tend as required to allow carbonation. Please see technical data sheet.
- Apply a breathable paint such as Earthborn Clay Paint, BEECKs Maxil or Graphenstone.
- The application of lime plaster is more involved than using conventional plaster. It is highly recommended to use a builder experienced in the use of lime plaster or at the very least you should get some practical experience e.g. on a course, as it is not possible to cover every point in detail here.
However, if you need further guidance after following the advice given, please contact our Product Support Team at tymawr@lime.org.uk or 01874 611 350