Preparation for repointing: brickwork cleaning.
In some instances, especially where pollution staining is prevalent, before any repointing can be undertaken dirty brickwork will require professional cleaning. The process is high in significant health risks and it is not a DIY procedure with cleaning products only available from specialist suppliers.
Nevertheless, if the cleansing phase is missed out the upshot can be a very poor finish.
The building on the right has been cleaned using the appropriate acid and all pollution staining has been removed. This has been followed by repointing with the correct NHL mortar.
Reasons for professional cleaning:
- atmospheric soiling is not water soluble
- abrasive cleaning is frequently damaging and generally best avoided
- cleaning chemicals must be used at low strength, applied neatly, left for short dwell times and thoroughly rinsed at non-damaging pressures.
Blasting: We also do soda blasting and clean exposed woodwork and fireplaces.
Rendering and plastering:
Harl coats for cob and other friable and soft surfaces. Often used to control suction for general rendering.
Scratch coats for plastering and rendering
Second coats/holding coats
Natural Roman Cement Stucco - exterior lime cement
Internal plastering using chalk, sand, hemp and marble.
- Chalk has insulating properties.
- We work with ready pigmented plasters.
- We also work with polished plaster and clay plaster.
- We can also lime skim over damaged substrates by first ---- applying specialist primers.
We work with insulating plasters mainly of our own design. These increase U values considerably. We also work with many premixed plasters including haired chalk for application on to lath.
A little about sustainable building materials:
The construction and maintenance of dwellings has changed dramatically over the last 20 years. When I first started everything was sand, cement (with a squirt of Fairy Liquid) and thermoset plastic insulation such as Celotex and Kingspan. Not much thought was given to ecological soundness or sustainability where the built environment was concerned. Back in the day it was difficult to even buy a bag of lime.
Now the internet is flooded with online retailers selling all manner of lime products, alternatives to lime and other sustainable materials. Simply put, the reason for this is because people are now more aware that quick and cheap products can often harm their homes.
Take cement for example. At one time hailed as the low cost panacea for all ills it is now seen as a damaging agent which is held in distain by many.
The building techniques and products of the 70s and 80s are now held onto only by those who cannot or will not change with customer demand. It's the same with builders' merchants. Demand for the bog standard staples of the construction industry such as cement, plasterboard, Cellotex, Thistle MultiFinish and building sand remains constant. Try obtaining Rowland Premix, Hemp shiv, insulating plaster or natural cement and see how far you get. You'll be lucky if you can find breathable paint.
This will eventually change because the change has already taken place. We're just waiting for the builders and their suppliers to wake up.
Take the manufacture of hemp for example:
British growers have been farming and promoting hemp for plastering, building and flooring for an increasing number of years and those who work with (and specify) for period properties are now leaning further towards this ecologically sustainable product.
Hemp is used instead of sand for internal render mortar because it is renewable and provides a highly efficient degree of thermal insulation.
I have spent years working with lime mortar and usually find myself far too busy to offer any other service besides stone and brick masonry. However, enthusiasm always gets the better of me and I now find myself unable to resist offering the ecological alternative to lime plaster.
After much time researching the best ingredients to go into a hemp shiv lime plaster mix I am pleased to announce that I'm now in a position to offer clients my own personal recipe. It's quicker to dry, more workable not subject to cracking.
Do bear in mind though, that hemp plaster takes a very long time to dry. If you allow a couple of months per coat then you'll be about right.