Extensions
A house extension is one of the most effective ways to create the space you need without the stress or cost of moving. At Mercer South, we specialise in bespoke house extensions across Hayling Island and Hampshire, helping families add light, space, and value to their homes. Whether you dream of a bright open-plan kitchen diner, an extra bedroom for a growing family, or a practical utility room, our experienced, family-run team brings the expertise to make it happen.
We know that every home and every family is different. That’s why our approach to a house extension is personal and flexible, tailored to your lifestyle and your property. From the first consultation, we take time to understand your vision and provide clear advice on design, planning permission, and building regulations. Our multi-trade team includes trusted builders, electricians, plumbers, and decorators, ensuring that every stage of the project is managed under one roof with consistent quality and attention to detail.
Based on Hayling Island, we work across Hampshire, including Portsmouth, Chichester, Southampton, and surrounding areas. Our local knowledge and strong supplier relationships mean we can deliver reliable service and competitive pricing without compromising on quality. Many of our clients come to us through recommendations, which we believe is the best sign of the trust and satisfaction we’ve built as a family-run company.
When you choose Mercer South for your extension, you’re choosing craftsmanship, reliability, and peace of mind. We manage everything from the groundwork and structural build through to finishing touches like flooring, lighting, and decoration. Our team keeps you updated throughout, so you feel confident and informed at every stage.
A well-designed extension doesn’t just add square footage — it transforms the way you live in your home. If you’re looking for a trusted building company on Hayling Island to deliver a seamless, high-quality extension, Mercer South is here to help. Get in touch today to start planning your project.
WHY CHOOSE US
With over 80 years of combined experience, we deliver expert construction services built on trust and professional integrity. We pride ourselves on a seamless process that prioritizes your vision and peace of mind. Our commitment to excellence is reflected in our core standards:
- Financial Responsibility to Our Clients
- Superior Quality and Craftsmanship
- Quality and Value to the Projects We Deliver
- Highest Standards in Cost Control
- On Time and on Budget
- Real Focus on Customer Satisfaction
POPULAR QUESTIONS
Not always. Many smaller extensions fall under “Permitted Development” rights, which do not require a full planning application. However, larger projects or those in conservation areas will likely need formal approval. We can review your initial ideas and advise on whether your specific project requires planning permission or a Lawful Development Certificate.
While every project is unique, a well-executed extension (such as an extra bedroom or a large kitchen-diner) can typically add between 10% and 20% to a home’s market value. With our 80 years of combined experience, we focus on designs that maximize both your living space and your long-term return on investment.
In most cases, yes. We take a “real focus on customer satisfaction” by managing the site to minimize disruption. We often use temporary hoarding to separate the living areas from the construction zone, ensuring your home remains clean, safe, and functional until the final “knock-through” occurs.
Seamless integration is a hallmark of our work. We go to great lengths to source matching bricks, mortar colors, and roof tiles to ensure the new structure looks like a natural part of the original building. Our goal is to create an extension that enhances your property’s character rather than looking like an obvious addition.
We’re a family of experienced builders with a team of project managers, and main contractors committed to delivering excellence in every project.
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