What are the most effective and safest ways to clean exterior brickwork and walls?
Gleam Team provide professional exterior cleaning and brick cleaning services in Kent, London and the south east. We specialise in:
- house and building exterior cleaning
- wall and brick cleaning
- render cleaning
- low pressure soft washing
- new builds post construction exterior cleaning
- removal of algae, lichen and mould from brickwork
Here at Gleam Team we believe in using low pressure soft wash water cleaning methods for exterior brickwork. Soft washing is a very low pressure method of cleaning outdoor areas that could be damaged by high pressure jet washing. Soft wash methods apply water and a suitable cleaning product at low pressure to gently but effectively clean fragile surfaces such as bricks, rendered walls and roof tiles.
Soft wash brick cleaning avoids saturating walls and stops water from penetrating brickwork as it can when blasted at with power washing. The 2012 Code of Practice for Cleaning and Surface Repair of Buildings in the UK advises that when cleaning house and building exterior walls it should be done using the minimum amount of water necessary and at the lowest possible water pressure.
Our brick cleaning services in Kent and London adhere to these principles and soft wash building cleaning pumps water out at lower pressure than a garden hose. We do, of course, offer professional pressure washing services for suitable areas like driveway and patio cleaning, but we do not jet wash brickwork. The likelihood of damaging the brick face or mortar joints is too high.
If the brick face is damaged and comes off it exposes the softer, more porous inner brick which will absorb rain and leave water trapped inside the brick. In winter weather this leads to a freeze and thaw cycle and frozen water expands in volume by 9% as it is explained in this article in Wikibooks.
This increase in volume can cause cracks and damage within the brick leading to more serious structural issues and damp problems. Excessive water can also activate soluble salts which leads to efflorescence deposits on the surface of the bricks.
The UK based Brick Development Association states
Pressure washing of older brickwork is never recommended
Brick cleaning techniques
Water cleaning
For the general cleaning of bricks and removal of dirt, grime and airborne deposits simple water cleaning will often be the first choice and most suitable method of brick cleaning.It poses very little risk of damaging brickwork or mortar but can be surprisingly good when combined with the right kind of detergent, and hot water makes the cleaning process even more effectve.
A stiff broom is then used to agitate the soapy solution after it has been sprayed over the wall and is then rinsed with plenty of clean water but without saturating the brickwork. Fibre bristles or a stiff nylon broom only should be used and never use a wire brush. Wire brushes can damage the brick and mortar and also leave metal filings in the brick causing metallic rust stains when exposed to rainwater.
When is the best time of year for brick cleaning?
If possible brick cleaning should be avoided during the coldest winter periods or if there is a likelihood of frost and freezing conditions for a 7 day period after the cleaning. Brick cleaning is best carried out during milder and drier weather in the spring or summer when there’s no chance of a freeze and thaw cycle.
Chemical cleaning
One of the most well known brick cleaning chemicals are those that are typically marketed as ‘Brick Cleaner’ or ‘Brick Acid’. these products in fact contain hydrochloric acid (also known as muriatic acid). There are many different types of brick acid on the market made by well known brands such as Bostik, Sika and Everbuild. Hydrochloric acid is extremely corrosive and should only be used by professional brick cleaners who know how to safely handle it and have the appropriate PPE.
Brick cleaning acid is often used for the removal of cement and mortar stains.
WARNING: Before applying hydrochlorric acid to brick walls or any other surface, the brick should first be wet with clean water to prevent the chemical being absorbed into the brick in large quantities. Acid MUST always be diluted before use and applied with care. Do NOT allow the chemical to dry on the brick as this may cause staining. Each treatment must be thoroughly rinsed with fresh water while it is still wet and before reapplying.
BRICK CLEANING ACID IS FOR PROFESSIONAL USE ONLY in the opinion of Maidstone Gleam Team. Some products, e.g. Bostik Mortar and Brick Cleaner is sold for ‘Trade Use Only’.
Tri sodium Phosphate (TSP) is another specialist brick cleaning chemical that is particularly suited to cleaning paint and other heavy duty staining from brick. It should be dissolved in warm water and carefully applied by brush.
New build apartment before efflorescence cleaning
Post construction new build cleaning services in Kent, London & south east
Gleam Team have experience of construction cleaning of the exterior areas of new build properties throughout Kent including an exclusive apartment block in Canterbury City centre and a recent project in Maidstone involving newly built 2 and 3 bedroom homes. Our builders clean for outdor areas includes:
- brickwork cleaning
- cement and mortar stain removal
- efflorescence removal
- graffiti paint removal and cleaning
Cleaning the external areas of new buildings is a specialist task that should be completed by experienced professional building cleaners who know how to safely and effectively clean and remove problem staining like hardened mortaar and cement and white efflorescence salts. These type of stains can seriously detract from the visual appeal of new builds.
If you own or manage any new build projects in Kent, London and the south east of England you will want the properties looking their absolute best when putting them on the market and Maidstone Gleam Team can help.
Areas we operate in include Maidstone, Chatham, Gillingham, Medway Towns, Ashford, Canterbury, Sittingbourne, Kings Hill, Malling, Tonbridge, Tunbridge Wells, Sevenoaks, Meopham, Gravesend, Dartford, Bexley, Bexleyheath, Welling, Eltham, Bromley, Chiselhurst, New Eltham and across south London.
Efflorescence cleaning & removal
Efflorescence is the white staining often seen on brickwork. It often appears on newly built brick walls but can also appear on older established buildings. The white marks are soluble salts located inside the brick or mortar joints that are activated by water and rise to the surface as the brick dries. They do not pose any structural dangers to brickwork but are unsightly and frustrating for property owners.
Efflorescence should slowly begin to fade through natural weathering and may eventually disappear on its own. However, there are no guarantees of that and it will very probably take a long time over a period of several years.
Before cleaning efflorescence we look for any potential sources of water ingress into the brick. Water is causing the problem so is rainwater able to easily penetrate the wall through holes in the brick, cracked or missing mortar joints, faulty flashing or some other way? If the source of the water can be identified it needs to be fixed and made waterproof.
However, there are many other ways that water may have got into the brick that will not be visible or obvious and are beyond your control. These include groundwater levels and construction techniques. This is particularly relevant for new buildings showing multiple patches of efflorescence staining. Pssible explanations could be something as simple as the storage location or waterproof covering coming off and exposing bricks to the elements.
But to a professional brick cleaning company like Gleam Team we have the experience and know-how to remove and clean away efflorescence staining from older or new brickwork of your house or commercial building. Our brick cleaning and post construction new build cleaning services are aavailable throughout Kent and London for residential and commercial customers. On occasion, for larger contracts, we have travelled further afield around the home counties including Surrey, Berkshire and Essex.
For further information or to arrange a FREE no obligation quote, or just to discuss your requirements please contact us using the Contact Us form or call 07581 681994.
References and sources for this post:
- 2012 Code of Practice for Cleaning and Surface Repair of Buildings (31 July 2012)
- Inspectapedia – Stains on brick surfaces (date published unknown)
- Brick Development Association – Cleaning of Clay Brickwork (November 2017)