--- title: "Raft Foundations vs Strip Foundations — Which Is Right? | Masters Group" description: "Compare raft and strip foundations for your Brighton build. Learn when each type is suitable, cost differences, and how East Sussex soil conditions affect your choice." lang: en json-ld: | [ { "@context": "https://schema.org", "@type": "BlogPosting", "headline": "Raft Foundations vs Strip Foundations: Which Is Right for Your Build?", "description": "Comparing raft and strip foundations for Brighton builds including costs and soil conditions.", "datePublished": "2025-01-22", "dateModified": "2025-01-22", "author": { "@type": "Organization", "name": "Masters Group" }, "publisher": { "@type": "Organization", "name": "Masters Group", "url": "https://mastersgroup.uk", "logo": { "@type": "ImageObject", "url": "https://mastersgroup.uk/images/hero-bg.jpg" } }, "mainEntityOfPage": "https://mastersgroup.uk/blog/raft-foundations-vs-strip-foundations", "image": "/assets/foundations-DibUBCQ2.jpg" }, { "@context": "https://schema.org", "@type": "FAQPage", "mainEntity": [ { "@type": "Question", "name": "Which foundation type is cheaper?", "acceptedAnswer": { "@type": "Answer", "text": "Strip foundations are generally cheaper for simple builds on stable ground. However, raft foundations can be more economical on difficult sites by reducing excavation costs." } }, { "@type": "Question", "name": "How do I know which foundation I need?", "acceptedAnswer": { "@type": "Answer", "text": "A site investigation (trial hole or bore hole) reveals ground conditions, and your structural engineer will specify the appropriate foundation type." } } ] }, { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://mastersgroup.uk/" }, { "@type": "ListItem", "position": 2, "name": "Blog", "item": "https://mastersgroup.uk/blog" }, { "@type": "ListItem", "position": 3, "name": "Raft vs Strip Foundations" } ] } ] --- 17 Colebrook Road, Brighton, BN1 5JH info@mastersgroup.uk [![Masters Group](/assets/masters-logo-Dn445ZsE.png) MASTERS GROUP ](/) [Home](/)[About](/about) Services Areas [Our Work](/our-work)[Warranty](/warranty)[Reviews](/reviews)[Blog](/blog)[Contact](/contact) [01273 110607](tel:01273110607)[Get Estimate](/contact) ![Foundation construction in Brighton — comparing raft and strip foundation types for East Sussex builds](/assets/foundations-DibUBCQ2.jpg) - [Home](/) - [Blog](/blog) - Raft vs Strip Foundations Foundations # Raft Foundations vs Strip Foundations: Which Is Right for Your Build? Published 22 January 2025 · 9 min read Choosing the right foundation type is one of the most important decisions in any construction project. The two most common options for residential builds in [Brighton](/areas/brighton) and [East Sussex](/areas/east-sussex) are raft foundations and strip foundations. Each has distinct advantages depending on your site conditions, building type, and budget. ## What Is a Strip Foundation? Strip foundations are continuous strips of concrete that run beneath load-bearing walls. They transfer the weight of the structure to the ground along these linear paths. Strip foundations are the traditional choice for most UK residential buildings and are effective when ground conditions are stable and consistent. For most [standard foundation projects](/services/foundations) in Brighton, strip foundations are cost-effective and well-understood by building control. ## What Is a Raft Foundation? A [raft foundation](/services/raft-foundations) is a large concrete slab that spans the entire footprint of the building. It spreads the load across a much wider area, making it ideal for sites with weaker or variable ground conditions. Raft foundations are increasingly common in Brighton, particularly on clay soils or sites near trees. ## Key Differences Factor Strip Raft Best for Stable, consistent ground Weak or variable ground Depth Typically 600mm–1m+ Shallower, 300–500mm Excavation Trenches only Full footprint Cost Lower for simple builds Higher material cost, but can save on excavation Speed Standard Often faster overall ## Soil Conditions in East Sussex Brighton and surrounding areas sit on varied geology. The chalk downland provides excellent bearing capacity in many locations, but areas with clay—particularly Weald Clay in [Haywards Heath](/areas/haywards-heath), [Burgess Hill](/areas/burgess-hill), and [Horsham](/areas/horsham)—can be prone to shrinkage and heave, making raft foundations the safer choice. ## Which Should You Choose? The decision ultimately comes down to a site investigation. A trial hole or bore hole reveals ground conditions, and your structural engineer will specify the appropriate foundation type. At Masters Group, we carry out foundation assessments as part of our [new build](/services/new-builds) and [extension](/services/extensions) services, ensuring the right solution from day one. For a detailed cost breakdown, see our guide: [new build costs in Brighton](/blog/how-much-does-a-new-build-cost-in-brighton). ### Need Foundation Advice? We assess ground conditions and recommend the most suitable and cost-effective foundation solution for your project. 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