My experience with The Market Design and Build regarding the installation of our boiler has been deeply disappointing. During the annual service, the boiler company, Vaillant identified critical installation defects--including an undersized gas pipe, unsecured flue pipe, and inaccessible flue endpoint.
Despite raising these concerns immediately in June 2024, no corrective action was taken. When the boiler was serviced again in May 2025, Vaillant issued a Second Warning Advice Notice, confirming that the same defects remained unresolved. If left unaddressed, these issues risk voiding the boiler's 10-year warranty and may require escalation to the Gas Safe Register.
I contacted Aaron, the Director of the company, multiple times--via calls and emails--requesting timely remediation, but my communications have gone unanswered. This lack of response and accountability is highly concerning.
Choosing a reliable service provider is crucial, and based on my experience, I strongly advise prospective customers to conduct thorough due diligence before engaging with this company.
I have written another Google review about The Market Design and Build and included photos as evidence to support my concerns, ensuring that my statements remain factual and not defamatory. read more