Just a few brief thoughts about the practicality and timescales when using lime based building products.
- Lime is “slow” building and plastering which means that build timescales are extended over conventional products. Usually at least a week will be required between coats ; this may be extended during colder/damper weather.
- Moisture is required for the correct carbonation of lime mortars and plasters which leads to longer drying times and delayed periods before the application of paint finishes.
- Temperature and prevailing weather affect external rendering to the extent that this type of work should only be undertaken from april- sept…..local conditions prevailing. To ensure the lime product does what it needs to do, remains fit for purpose and looks aesthetically correct, there are often a number of processes that are essential and can’t be short cut. ie: the correct number of coats at the right thickness using the correct type of lime and aggregate and applied in the correct way under appropriate conditions.
- Beware of builders who say that they are familiar with lime………i hear horror stories of renders falling off, cracking and failing……… poor and innapropriate mixes ………insuffucient protection dampening and aftercare………shortcuts and handfulls of cement in the mix to help “harden it up”.
I always detail the exact number of coats ; the specification of each plaster/render coat and the care and timescale of each process. Renovation can be disruptive especially if you are living in a property under renovation and the clearer the timescales and processes are the easier the project will be.