National construction quality learning
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34 published lessons
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4 lifecycle stages
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34 results
Published lessons
NCQLE-2026-00035
Poor Installation of a One-Hour Fire-Resisting Wall
Poor installation practices were identified around an opening within a one-hour fire-resisting plasterboard wall. The boards have damaged and broken edges, irregular joints, narrow infill pieces, inconsistent fixing pos… Workmanship and installation Commercial
NCQLE-2026-00034
Poor Firestopping Around Hospital Service Penetrations
Poorly executed firestopping was identified around a plastic waste pipe and copper medical-gas pipework within a hospital ceiling void. The installation appears irregular and incomplete, with visible gaps and no clear e… Workmanship and installation Healthcare
NCQLE-2026-00033
Reinforced Concrete Transformer Base Installed in the Wrong Orientation
The reinforced concrete base for the high-voltage transformer was set out and constructed in the wrong orientation. As a result, the transformer support frame and associated equipment did not achieve the required bearin… Workmanship and installation Healthcare
NCQLE-2026-00032
Structural Beams Incorrectly Connected and Misaligned
Two structural steel beams were connected at different levels, creating an approximate 10 mm offset between their upper flanges. The connection appears to have been assembled incorrectly or fabricated without achieving … Workmanship and installation Education
NCQLE-2026-00031
Electrical Conduit Improperly Secured to Medical Gas Pipework
Zinc-plated electrical conduit was secured directly to copper medical gas pipes using adhesive tape instead of being independently supported. Medical gas pipework must not be used as a support for electrical services or… Workmanship and installation Healthcare
NCQLE-2026-00029
Structural Lintel Omitted Above Reduced Window Opening
The window openings were constructed smaller than the formed structural lintel . Instead of resolving the dimensional discrepancy through an approved redesign, additional masonry or infill was constructed above the wind… Workmanship and installation Commercial
NCQLE-2026-00028
Electrical Socket Positioned Directly Behind a Hob
A double electrical socket and associated controls were installed immediately behind the cooking hob. Any appliance connected at this location would require its flexible lead to pass close to, or potentially across, the… Workmanship and installation Residential
NCQLE-2026-00027
Oversized Openings Around Electrical Back Boxes
Circular openings were cut into the plasterboard significantly larger than the square electrical back boxes. This left unsupported gaps around the boxes that could not be properly covered or sealed by the finished acces… Workmanship and installation Residential
NCQLE-2026-00026
Non-Compliant Plug Used for Aerial Amplifier
An aerial amplifier within the electrical riser of a newly constructed residential block was connected to a UK socket using a non-BS 1363 plug. The two-pin plug appeared to have been inserted directly into the socket wi… Testing and commissioning Residential
NCQLE-2026-00025
Incorrect Formwork and Reinforcement Positioning
The concrete upstand or kicker was formed out of alignment with the reinforcement cage, leaving the starter bars positioned close to one edge rather than centrally within the intended concrete section. If the next concr… Workmanship and installation Commercial
NCQLE-2026-00024
Loose Structural Steelwork Fixing
A structural bolted connection was found with the nut and washer not fully seated against the steel plate, leaving a visible gap. This indicates that the fixing may not have been correctly tightened or may have loosened… Inspection and quality control Residential
NCQLE-2026-00023
Corrosion Protection Failure to Cut Structural Bolts
Structural steelwork bolts were cut down with a grinder after installation, damaging or removing the protective coating from the exposed threaded ends and adjacent nuts. The untreated surfaces have subsequently corroded… Workmanship and installation Residential
NCQLE-2026-00022
Inaccessible Basin Waste Trap Concealed Within Wall
The basin waste trap was installed within the wall construction without a suitable access panel or other means of safely inspecting, cleaning or servicing it. Any future maintenance or blockage removal would require the… Workmanship and installation Healthcare
NCQLE-2026-00020
Cable Tray Resting on Copper Medical-Gas Pipework
Zinc-plated electrical cable trays were installed in direct contact with and supported by copper medical-gas pipes. Medical-gas pipework must not be used to support electrical containment, and each service should have i… Workmanship and installation Healthcare
NCQLE-2026-00019
Incorrect Back Box Installed in a 60-Minute Fire-Resisting Wall
An incorrectly sized plastic electrical back box was installed within a 60-minute fire-resisting plasterboard wall instead of the specified metal back box. To make the retaining lugs engage, the installer broke away and… Products and materials Commercial
NCQLE-2026-00018
Plastic Packers Used in Structural Lift-Shaft Steelwork
Plastic packers were found between structural steel components within the lift shaft, where steel finger packers or engineered metal shims should have been used. Unless specifically designed and approved for the applica… Products and materials Healthcare
NCQLE-2026-00017
Gas Supply Pipe Installed Without a Protective Sleeve
The gas supply pipe to a newly built house appeared to pass directly through the external cavity wall without a suitable continuous sleeve. Mortar had also been applied directly around and onto the copper pipe. This ins… Workmanship and installation Residential
NCQLE-2026-00016
Incorrectly Sized and Inadequately Fixed Fire Doorset
The fire doorset appeared to be undersized for the structural opening, resulting in an excessive gap between the frame and the supporting wall. The gap had been built out using multiple layers of plasterboard and intume… Workmanship and installation Healthcare
NCQLE-2026-00015
Incorrect Installation of an Open-State Cavity Barrier
The intumescent open-state cavity barrier was installed too far forward and finished flush with the vertical cavity barrier. Once the façade panels were installed, the barrier would press tightly against the rear of the… Workmanship and installation Residential
NCQLE-2026-00014
Glazed panels installed wrong way round
During inspection of the completed façade, several glazed panels appeared to have been installed the wrong way round. This was evident from the significant variation in colour and reflectivity, with some panels displayi… Workmanship and installation Commercial
NCQLE-2026-00013
Premature Corrosion of Powder-Coated Rainscreen Panels
Significant areas of corrosion were identified on aluminium rainscreen panels only eight years after installation. Investigation indicated that the powder-coating thickness was below the specified requirement, resulting… Products and materials Residential
NCQLE-2026-00012
Porus Panels install on UK rail infrastructure project
During the inspection of porous architectural wall panels installed on a major UK rail infrastructure project, significant vertical staining, water marks and colour variations were observed across the completed finish, … Products and materials Rail and transport
NCQLE-2026-00009
Incorrect Materials installed in Facade Framework
The façade support framework had been assembled using small aluminium angles and flat aluminium strips instead of the specified structural T-sections required to support stone panels weighing approximately 100 kg each. … Workmanship and installation Commercial
NCQLE-2026-00008
Incorrect Install of Intumescent open state fire barrier
A short section of the open-state intumescent cavity barrier appears to have been friction-fitted between a continuation of the barrier, with no visible mechanical fixing. The installation may therefore rely on the plas… Workmanship and installation Residential
NCQLE-2026-00006
The brick arch appears structurally unsafe.
The brick arch appears structurally unsafe. Perforated bricks have been laid in an unsuitable orientation, mortar joints are irregular and incompletely filled, and the crown lacks a properly formed and bonded keystone a… Workmanship and installation Commercial
NCQLE-2026-00005
The brickwork demonstrates poor workmanship
The brickwork demonstrates poor workmanship, including irregular and incomplete bed and perpend joints, excessive mortar voids and inadequate bedding around the wall ties. The ties appear to have been installed in the w… Workmanship and installation Commercial
NCQLE-2026-00004
Covering up the Fire cavity Barrier face with foil Tape
The cavity barrier face has been covered with foil tape, apparently masking an inadequate fit rather than correcting it. Foil tape cannot replace the required physical contact and compression between a closed-state cavi… Workmanship and installation Residential
NCQLE-2026-00003
Fire Cavity Barrier hanger failure after 8 years
The cavity-barrier support hanger has suffered severe premature corrosion after approximately eight years, with extensive rusting, delamination and apparent loss of metal section around the fixing and along the support.… Products and materials Residential
NCQLE-2026-00001
Encapsulation of Combustibles using EPDM membrane
It was found that the Facade contractor was using EPDM membrane to encapsulate Combustible materials around windows on a HRB over 18M. No update from Fire engineer and no valid fire engineer report available Clien… Products and materials Residential
NCQLE-2026-00030
Incorrect Junction Between Open-State and Vertical Fire Barriers
The corner junctions between the horizontal open-state cavity barrier and the vertical fire barriers around the window were installed incorrectly and did not follow the manufacturer’s approved design. The barriers were … Workmanship and installation Residential
NCQLE-2026-00011
Structural bracket made up on site with poor welding
A support bracket for a glass balustrade installed more than 18 metres above ground level appeared to have been fabricated or modified on site and did not match the approved design. The welded connection showed poor wor… Workmanship and installation Residential
NCQLE-2026-00010
Severe undercut on Structural Steel BMU Bracket
Severe undercut was observed along the toe of a fillet weld connecting a structural steel bracket. The undercut reduces the effective thickness of the parent material and creates a stress concentration that may initiate… Workmanship and installation Residential
NCQLE-2026-00007
Incorrect placement of Intumescent Fire batt and Bracket
The open-state cavity barrier appears to be incorrectly positioned against the façade C-channel rather than installed in accordance with the approved supporting-substrate detail. The façade carrier bracket obstructs the… Workmanship and installation Residential
NCQLE-2026-00002