Choosing a Contractor
Many in this industry make ridiculous claims about their systems and the problems that other companies are likely to create. Some claim they invented the system or give false information regarding their competitors. There have been companies in this industry that appear only to liquidate some time later, or change their name or company status to avoid claims. The most significant point to note is that the quality of the company you employ is most important as most systems work when applied correctly.
We encourage all our prospective clients to seek independent advice rather than conflicting opinions from contractors.
Items to consider are:
- Only the fully registered companies offer the complete service of damp coursing and re-plastering, and consequently guarantee the whole project. This is important as any company not prepared to quote on the total job has some else to blame when there is a failure. You would have to prove who is at fault.
- Damp plaster work is removed as soon as possible to allow the wall to dry. Saturated wall plaster only inhibits the drying out process. Saturated plaster work will not draw salt out of the wall.
- Pressure injection techniques are usually with spirit based products (including low odour ) as excess moisture is then pushed out of the walls and replaced with the silicone solution.
- Water based products have larger particle sizes and do not penetrate masonry readily. They are used for gravity or low pressure injection into the mortar joint where pore sizes are larger and natural diffusion takes place.
- Gravity feed systems using spirit based products have limited success as hydrocarbons have a specific gravity approx. 70% of water. Gravity feed solutions cannot push out the excess moisture as the product is lighter than water and will not mix. Penetration into the mortar joint is possible but not into the surrounding masonry substrate.
- Mortar joints are usually furrowed, have gaps, and are of soft materials, any injection into the mortar joints may be best performed by gravity feed with water based silicone solutions.
- Cutting out mortar joints and replacing mortar can cause movement of bricks especially where lime mortar is used.
- Electo-osmosis methods are a constant monitoring system, if the power supply fails, the wall surface may need repair again. Damp Guard prefer the ‘belts and braces’ approach to eliminate the likely hood of future problems. Electrical systems in the past have been plagued by corrosion of elements as well.
- Siloxane injection methods are the most economical and least destructive of the damp coursing methods, membrane replacement methods are 2 to 3 times the price for no added advantage.