Council Housing Render Cleaning Programme - Northampton (2024-2025)

Throughout 2024-2025, we had the opportunity to enhance our expertise through several commercial render-cleaning jobs for Northampton City Council, cleaning multiple residential buildings around Northampton. The goal couldn’t have been clearer: we had to remove heavy organic staining and weathering. Without disrupting residents’ lives, we aimed to make the facades look cleaner, brighter, and more evenly coloured.

You can see from the pictures that we had to address the typical issues with multi-storey blocks - green and black algae streaks concentrated beneath rooflines, around window bays, and down elevations near rainwater pipe runs. After cleaning, the buildings showed a more uniform appearance. Whether from street-facing or courtyard-facing elevations, they simply looked well-maintained.

Programme Overview

• Client: Northampton City Council
• Area: Northampton (multiple sites)
• When did we do it: 2024-2025
• What type of building: Multi-storey residential blocks (mixed elevations)
• The main surfaces we’ve cleaned: Rendered facades, cladding/uPVC panel sections, brick bases, window bay surrounds
• Contamination we had to address: Algae/organic growth, runoff streaking, general exterior soiling
• Access and control: For upper elevations we used long-reach cleaning, with targeted ladder access where safe, and controlled work zones near entrances and walkways

What did we clean

As seen in the site photos, the scope was similar to that of other projects: we had to remove algal staining and patchy weathering from the rendered wall elevations. Streaking was easy to notice on the white cladding and panel sections beneath and around the windows. Detail areas too - window surrounds, junction lines, and downpipe-adjacent staining - everything that typically collects runoff and grime. Nothing new to us.

Shade and moisture retention were also at play. Many of the blocks were near trees and green spaces. Left unaddressed, those are the perfect conditions for organic growth to return.

The Challenge

With council and housing properties, some realities stay the same. Across several elevations and blocks, we typically see the same staining patterns, and staining is common beneath parapets/eaves and along drainage routes. We have to clean without affecting residents’ lives - while we work, they should remain able to use entrances, access routes, and courtyards. Last, but not least, the finish has to be even. Patchy cleaning is out of the question; it reads as “unfinished”.

Our Approach

We started by examining the surface type (render vs panel). We also took a good look at the soiling pattern. Once we had all the information, we decided on the safest and most effective cleaning technique. Uniform results on large facades - that’s what we aimed for.

In areas where we had to address organic growth (algae or green staining), we followed a strict three-step process: controlled application, dwell time, then rinse. Aggressive blasting wasn’t the solution - it would have damaged the finishes and pushed water behind the panels.

Working meticulously is key to avoiding streaking and missed sections, and that’s exactly what we did. We paid attention to the window bays, junction lines, and pipework - practically anywhere grime and runoff staining show the most.

We don’t leave when the surface is still wet - we’re not done yet. Once the surfaces settled, we made sure everything looked consistent. Even from ground level, the finish should look even. That’s what residents and visitors will see, right?

What we have achieved

Across the programme, the facades took on a cleaner, brighter, and more uniform appearance. They no longer looked heavily streaked and weathered. The most impressive differences were on the upper bands beneath rooflines and on the cladding/panel areas around windows. The long runs of render, once marked by buildup streaking, also impressed - like new.

The methods

We turned to render-safe cleaning methods to remove organic staining without damaging the finishes. For the upper storeys, our teams used long-reach access, and wherever safe they set up targeted ladders. To avoid patchy results on large facades, we kept a consistent elevation-by-elevation pace. That’s how it’s done.

Related Services

• Render Cleaning
• Cladding and Facade Cleaning
• Commercial Exterior Cleaning