Removing Paint from Brickwork with Shot Blasting

Painted brickwork can completely change the appearance of a building.

Sometimes that painted finish is deliberate and remains perfectly serviceable for decades. In other cases, years of repainting leave a façade covered by several generations of coatings, some firmly attached and others peeling, flaking or failing.

Eventually, the property owner, managing agent or contractor may decide that the wall needs to be stripped back and properly prepared.

On suitable brickwork, controlled shot blasting or abrasive blasting can form part of that preparation process.

But the key word is controlled.

Brickwork is not structural steel. Older bricks, mortar joints, repairs and architectural details all need to be considered before deciding how the surface should be prepared.

Why Remove Paint from Brickwork?

There are several reasons a building owner may want old paint removed.

• The existing coating may be peeling or failing
• Several layers of old paint may have accumulated
• The original brick appearance may be required again
• A façade may be undergoing wider restoration
• The property may need preparing for a completely new coating system
• A commercial building may be changing ownership, use or brand

The required finish should be understood before the preparation work begins.

Preparing brickwork that will ultimately be repainted is not necessarily the same task as restoring brickwork that will remain exposed.

Paint Can Hide What Is Happening Underneath

An old painted façade can conceal a surprising amount of history.

Once coatings begin to come away, the wall may reveal different brick types, historic repairs, replacement bricks, changes to openings, old fixing points or mortar that has been repaired at different times.

That is particularly common on older London properties where buildings may have been altered repeatedly over a century or more.

Can Shot Blasting Remove Paint from Brickwork?

On appropriate brick and masonry surfaces, carefully controlled blasting can help remove old coatings and expose the underlying substrate.

However, not every painted brick wall should automatically be blasted.

The contractor needs to consider:

• The age and hardness of the brick
• The condition of the brick face
• The mortar joints
• The type and thickness of the paint
• Previous repairs
• The final appearance required

A hard modern brick can respond very differently from an older, softer Georgian brick.

Brickwork Preparation Is About Restraint

The objective is not to use the most aggressive setting possible and remove everything at maximum speed.

The objective is to remove the unwanted coating while retaining the material that should remain.

That distinction is particularly important on older façades.

Our dedicated brickwork shot blasting services are therefore based around assessing the substrate and matching the preparation method to the building.

Georgian and Period Brickwork

London contains large areas of Georgian and other period brick property.

These buildings can contain softer masonry, historic mortar, old repairs and decorative details that require considerably more judgement than modern industrial surfaces.

A small test area can be valuable before wider work begins.

This allows the building owner and contractor to see how the coating responds and what the brickwork beneath actually looks like.

Several Layers of Paint Can Create a Different Challenge

Some façades have been painted repeatedly for decades.

One layer may be well bonded while another has already failed.

Different coating systems may also have been applied on top of one another.

In these circumstances, preparation needs to consider the complete coating build-up rather than simply removing whatever is visibly loose.

Paint Removal Is Different From Render or Pebbledash Removal

This is an important distinction.

Shot blasting can be used, where appropriate, to remove paint and coatings from suitable brickwork.

It is not normally the primary method used to remove the bulk pebbledash or render system from a building.

Where a property is rendered or pebbledashed, the main outer finish would generally be removed mechanically first.

Once that has been done, the exposed brickwork may still contain residual render, old masonry paint or other firmly bonded coatings.

Specialist blasting may then become relevant as a follow-on preparation stage.

Preparing Brickwork for Repainting

Many projects are not about revealing bare brick permanently.

The owner may simply want the failing coating removed so the building can be properly repaired and repainted.

That changes the objective.

The aim is to create a stable, suitably prepared substrate for the coating that follows.

Depending on the building, this may also involve:

• Brick repairs
• Repointing
• Local making good
• Removal of loose material
• Cleaning before repainting

Why Simply Painting Over Failing Paint Can Be a Problem

A new coating is only as secure as the layers beneath it.

If loose or poorly bonded paint remains, another coating over the top may simply inherit that weakness.

This is why preparation can account for such a significant part of a refurbishment project.

Removing Paint to Restore Exposed Brick

Some property owners want to remove paint because they want the original brickwork visible again.

That changes the standard against which the preparation needs to be judged.

The finished brick itself becomes part of the appearance of the building.

Older masonry may naturally show:

• Colour variation
• Historic repairs
• Replacement bricks
• Weathering
• Evidence of previous alterations

These are not necessarily problems.

They can form part of the character of the building.

Do Not Over-Restore Historic Brickwork

There can be a temptation to keep blasting until every visible trace of age or previous work disappears.

That is not always appropriate.

Particularly on older masonry, the aim may be to remove the unwanted coating while avoiding unnecessary erosion of the original brick face.

More aggressive does not automatically mean better.

Test Areas Can Be Valuable

Where the façade is old, highly visible or architecturally important, a controlled test area can help establish:

• How readily the coating comes away
• How the brickwork responds
• What historic repairs become visible
• What the likely finished appearance will be

This can help avoid surprises once the wider façade is prepared.

Property Restoration Is Often a Sequence of Specialist Trades

On a larger project, shot blasting may be only one stage.

The complete programme may involve:

• Scaffolding
• Coating removal
• Masonry repairs
• Repointing
• Surface preparation
• Painting or another final finish

Where appropriate, preparation can also be coordinated with our industrial and commercial painting services.

Commercial and Industrial Brickwork

Painted brickwork is not limited to residential buildings.

Factories, warehouses, workshops and commercial premises can also contain painted internal or external brick surfaces requiring refurbishment.

On industrial sites, the requirement may be part of a much larger maintenance or redevelopment programme.

The same basic rule applies: understand the substrate and what finish needs to follow before selecting the preparation method.

London Property Work Needs Practical Planning

Surface preparation on a London property may involve practical issues well beyond the brickwork itself.

These can include:

• Scaffolding
• Neighbouring properties
• Pedestrians
• Vehicles
• Restricted access
• Working hours
• Containment and housekeeping

This is one reason mobile shot blasting needs to be treated as part of the overall building project rather than an isolated process.

Working on Occupied Properties

Some buildings remain occupied throughout the refurbishment.

The work may therefore need to be planned around residents, employees or customers.

Access, noise, dust control and the sequence of work all need to be considered alongside the technical preparation itself.

Working With Main Contractors and Property Managers

On larger projects, Intercity Contractors may be appointed by a property manager, facilities-management company or main contractor rather than directly by the building owner.

In those circumstances, our preparation work forms one specialist package within the wider programme.

You can read more about this in our guide to shot blasting subcontracting for property managers and main contractors.

Removing Paint Without Losing the Character of the Building

There is a difference between preparing an old wall and trying to make it look as though it was built yesterday.

Particularly on Georgian and other period buildings, the surface may naturally carry evidence of its age.

The appropriate finish may retain some of that variation while still removing the unwanted paint or failed coating.

The preparation method should reflect what the building owner is ultimately trying to achieve.

Shot Blasting Painted Brickwork

When used appropriately, controlled blasting can be an effective part of removing old paint and coatings from suitable brickwork.

The successful project is not the one where the surface has simply been blasted hardest.

It is the one where the unwanted coating has been removed and the brickwork has been left in the right condition for whatever happens next.