Build Systems &
Low-Carbon Methods
We build with five core systems — and we'll explain, in plain English, which one suits your home, your budget, and your carbon goals.
The right method for the right job.
Building materials account for a huge share of a home's lifetime carbon footprint. Choosing low-carbon, modern methods of construction — alongside traditional craft where it counts — lets us build better-performing homes with a smaller environmental impact. We'll walk you through every option before we build.

Six Build Systems
Hover any card to explore — each links to a deeper specification.
Brick & Block
The Hampshire classic. A masonry cavity wall with an outer brick skin and inner block, filled with insulation. Robust, familiar, and ideal for traditional aesthetics and conservation areas.
- Traditional appearance
- Excellent thermal mass
- Conservation-area friendly
Modular Construction
Factory-built room modules delivered and craned into place, dramatically reducing on-site time, waste and disruption. Pre-insulated, precision-engineered, and quality-controlled off-site.
- Up to 60% faster on site
- Minimal disruption
- Factory quality control
Metsec Steel Framing
Lightweight galvanised steel framing systems that allow large open spans and fast erection. Perfect for loft conversions, extensions and structures where speed and strength matter.
- Large open spans
- Fast erection
- Lightweight & strong
SIP Panels
Structural Insulated Panels — high-performance factory panels that form walls and roofs in one thermally efficient layer. Outstanding airtightness and the lowest U-values per unit thickness.
- Superior insulation
- Excellent airtightness
- Lower embodied carbon
Timber Frame
Renewable, low-carbon engineered timber framing that's fast to erect and endlessly adaptable. A natural choice for sustainable extensions with a warm, honest character.
- Renewable material
- Fast construction
- Low embodied carbon
Hybrid Systems
We're not dogmatic. Many of the best projects combine systems — a brick frontage, a SIP rear, steel-framed glazing. We specify the right material for each part of the build.
- Tailored per project
- Best of every method
- Performance-optimised
Typical Construction Details
A practical breakdown of how each building element is constructed in England — the materials, dimensions and regulations behind a well-built home.
Below Ground Drainage
Foul and surface water drainage below ground in England is typically laid in plastic (uPVC) or vitrified clay pipework, bedded on granular material and fall-tested to maintain self-cleansing flow.
- uPVC (BS EN 1401) or vitrified clay (BS EN 295) pipes, 100mm–150mm dia.
- Minimum fall of 1:40 (100mm) / 1:80 (150mm) for foul drainage
- Inspection chambers (rodding points) at every change of direction
- Soakaways or connection to mains sewer for surface water
- Building Regulations Part H approval required
Ground Bearing Floors
Most domestic ground floors in England are solid concrete slabs cast onto a prepared hardcore bed, separated by a damp-proof membrane and insulated in line with Part L.
- 150mm compacted hardcore (MOT Type 1) blinded with sand
- 100mm concrete slab (GEN1/GN1 mix) cast on DPM
- Rigid PIR insulation above or below slab per Part L
- Suspended timber or beam-and-block alternatives on poor ground
- Airtightness detailing at wall/floor junction critical
Shell Construction
The weatherproof envelope — walls, floors and roof — is built to create a weathertight, insulated box. In England this is most commonly a masonry cavity or timber/steel frame shell.
- Cavity wall: 102mm brick outer, 100mm block inner, full-fill insulation
- Timber frame: studwork sheathed with OSB, breather membrane, rainscreen
- SIP panels or Metsec steel for faster, lower-carbon shells
- Wall ties (stainless) at 900mm horiz / 450mm vert spacings
- Cavity barriers and fire-stopping at compartment lines
Window & Door Openings
Openings are formed with lintels over and cills below, with DPC detailing to direct moisture outboard of the cavity. Modern openings favour insulated frames and high-spec glazing.
- Catnic/masonry lintels with integral DPC tray over opening
- Sub-cill DPC lapped under cavity tray to prevent bridging
- Reveal closers maintain insulation continuity at jambs
- Double/triple glazed units, U-value ≤ 1.4 W/m²K (Part L)
- Trickle vents for background ventilation (Part F)
External Wall to Roof Junction
Where the wall meets the roof, the cavity is closed with a purpose-made tray, insulation continues to prevent cold-bridging, and the eaves detail manages ventilation and drainage.
- Cavity tray with weep holes above the wall plate
- Insulation carried up to ceiling/rafter line for continuity
- Eaves ventilation gap (25mm) for cold roofs, 50mm above insulation
- Fascia, soffit and guttering discharge rainwater to drainage
- Airtightness membrane lapped to ceiling vapour control layer
Pitched Roof Construction
Pitched roofs in England are typically timber trussed rafters or cut roofs, underfelted, battened and tiled. Insulation sits at ceiling level (cold) or rafter line (warm) to suit the loft use.
- Trussed rafters at 600mm centres, or cut rafters for conversions
- Breathable underlay (LR) over rafters, tiling battens at gauge
- Concrete or clay tiles on roofs ≥ 30°, slate on lower pitches
- Min 270mm mineral wool at ceiling level (cold loft)
- Rigid PIR between and below rafters for warm loft habitable use
Flat Roof Construction
Flat roofs are never truly flat — a fall of 1:40 directs water to outlets. Timber joists decked with ply/OSB are waterproofed with built-up felt, single-ply membrane or warm-deck insulation.
- Timber joists at 400mm centres, tapered firring for fall
- 18mm WBP plywood or OSB3 deck
- Warm deck: insulation above deck, membrane on top (preferred)
- Single-ply EPDM/TPO or 3-layer built-up bituminous felt
- Parapet upstand min 150mm, DPC dressed over tray
Internal Stud Walls & Finishes
Internal partitions use timber or metal studwork lined with plasterboard. Acoustic insulation and resilient bars satisfy Part E between rooms, with skim or taped-joint finishes.
- Timber stud 63×38mm or metal stud 50–70mm at 400/600mm
- 12.5mm plasterboard, two layers for acoustics
- Mineral wool in cavity for sound (Part E between dwellings)
- Plaster skim or tapered-joint drylining finish
- Door frames set out, architraves and skirings to complete
External Wall Finishes
The outer face is finished to shed water and deliver the aesthetic. Facing brick is the Hampshire default, with render, timber cladding or hanging tiles used for variety and economy.
- Facing brickwork in English/Flemish bond, pointing flush or weatherstruck
- Silicone or monocouche render on treated background
- Timber cladding on preservative-treated battens with breather gap
- Fibre cement or clay hanging tiles for upper-storey accents
- All finishes rely on a drained, ventilated cavity behind
Renewable Heating & Fabric
Plain-English explanations of the low-carbon technologies we install — each with a schematic diagram showing how it works in your home.
Air Source Heating & Hot Water
An air source heat pump (ASHP) extracts renewable heat from the outside air — even in winter — and upgrades it to warm your home and your hot water. For every 1 unit of electricity, it delivers around 3 units of heat, cutting running costs and carbon versus gas or oil boilers.
- SCOP of 3.0–4.5 (3–4 units of heat per unit of electricity)
- Works down to -20°C ambient air temperature
- Cylinder-based hot water with integrated coil
- Pairs with underfloor heating and low-temp radiators
- Low GWP refrigerant, MCS-accredited installation
Solar, Wind & Battery Inverter Systems
Solar PV and small-scale wind generation charge a battery bank through a hybrid inverter, storing surplus daylight energy for use at night. The inverter converts stored DC power to usable AC, reducing grid reliance and protecting against outages.
- PV arrays (monocrystalline) + optional micro wind turbine
- Hybrid inverter manages generation, storage and grid export
- Lithium battery storage (typically 5–15 kWh usable)
- Smart export of surplus to grid under SEG tariffs
- Backup power circuit for critical loads during outages
Ground Source Heat Pump
A ground source heat pump (GSHP) draws stable heat from the earth via a buried loop or borehole. With higher efficiency than air source, it delivers consistent heating and hot water year-round, with the lowest running costs of any renewable heating system.
- Horizontal trench loops or vertical boreholes (50–150 m)
- SCOP of 4.0–5.0 — highest efficiency renewable heating
- Consistent ground temperature year-round
- Ideal for new builds and larger plots
- Eligible for Boiler Upgrade scheme grant (£7,500)
Triple Glazing
Three panes of glass separated by two argon-filled cavities and low-emissivity coatings dramatically cut heat loss and draughts. Triple glazing achieves U-values as low as 0.6 W/m²K — roughly three times better than standard double glazing.
- U-value as low as 0.6 W/m²K (Part L future-proofed)
- Two argon-filled cavities between three panes
- Low-E coatings reflect heat back into the room
- Warm-edge spacers reduce cold bridging at the frame
- Improved acoustic insulation and comfort
Airtightness
Airtightness seals the building envelope against uncontrolled draughts and heat loss. A continuous airtight layer — membranes, tapes and sealants at every junction — is tested with a blower door to meet and exceed Building Regulations.
- Target ≤ 1.5 m³/(h·m²) @ 50 Pa (Part L: 8.0)
- Continuous airtight membrane at wall/roof/floor junctions
- Taped penetrations around services and openings
- Blower door test verifies build quality on completion
- Pairs with MVHR for controlled, low-energy ventilation
Power your home,
on or off the grid.
Solar panels and mini wind turbines generate clean electricity; a battery bank stores it; a hybrid inverter delivers 230V AC to your home — and can sit alongside a mains supply for the best of both worlds.
Solar PV Panels
Roof- or ground-mounted photovoltaic panels convert daylight into DC electricity. The primary generation source for most UK off-grid and hybrid systems, sized to match your daily load.
- Monocrystalline panels, 400W+
- Hybrid / off-grid compatible
- Works in overcast conditions
Mini Wind Turbine
A small (≤ 6 kW) horizontal- or vertical-axis turbine complements solar by generating at night and through winter storms — when PV output is lowest.
- 300W–6kW rated
- Ideal for exposed rural plots
- Pairs with solar for year-round yield
Battery Bank
Lithium-ion (LiFePO₄) or lead-acid batteries store surplus DC generation for use after dark or during low-wind lulls. Capacity is sized for your desired days of autonomy.
- Lithium LiFePO₄ preferred
- Modular, expandable capacity
- Charge controllers manage input
Inverter / Charger
The hybrid inverter converts stored DC battery power to 230V AC for your home, manages charging from solar/wind, and synchronises with a mains feed where one exists.
- Pure sine-wave 230V AC output
- Bidirectional (charges & inverts)
- Automatic mains/genset fallback
Three Ways to Connect
The same hardware can run fully off-grid, as a hybrid with mains backup, or grid-tied without storage. We size the array, battery and inverter to match how independent you want to be.
Off-Grid (Island Mode)
No mains connection at all. Solar + wind charge the battery; the inverter supplies the home from stored energy. A backup generator tops up the battery during long low-generation spells. Suited to remote rural plots and outbuildings with no grid feed.
Hybrid (Grid-Tied with Storage)
Mains remains connected as a backup. The system draws from solar/wind and battery first, only importing from the grid when the battery is low. Surplus generation can be exported (SEG tariff). Best of both — resilience and a grid safety net.
Grid-Tied (No Storage)
Simplest setup — solar (and wind via a grid-tie inverter) feed the home directly, with the grid covering any shortfall and absorbing surplus. No battery, lower cost, but no power during a grid outage.
Right-Sized for Your LoadWe model your daily energy use and generation profile to specify the correct panel, turbine and battery capacity — whether you want full independence or a resilient hybrid.
Control & Monitor Your Home
Know the status of your lighting, heating, security and power from one app — whether you're on the sofa or the other side of the world.

Lighting
Scene control, dimming and schedules per room.
Heating
Zoned underfloor heating and radiator control.
Security
Cameras, alarms, smart locks and access logs.
Power & Energy
Live consumption monitoring and appliance control.
How a smart home system works
Every smart home follows the same four-stage architecture — devices collect data, a backbone carries it, a hub processes it, and you control the result.
Sensors & Devices
Switches, thermostats, cameras and meters installed throughout the home.
Backbone
Devices communicate over PLC, wireless or a wired bus to a central hub.
Hub / Controller
The hub aggregates data and runs automations, scenes and schedules.
Remote Access
You monitor and control everything from a phone, tablet or voice assistant.
Programmable Logic Controllers (PLCs)
The "brain" behind an automation system — in plain English
A Programmable Logic Controller is an industrial-grade computer built to read inputs (switches, sensors), run a stored set of rules, and switch outputs (lights, pumps, motors) on or off — reliably, for years, without rebooting. In a smart home it plays the same role as the "hub", but it's specified when you want deterministic, hard-wired control: heating zones, fire misting, security interlocks, or whole-home automation that must not depend on Wi-Fi or an app.
The Three-Step Scan
A PLC doesn't run an app. It loops endlessly through three stages — reading every input, then deciding, then acting. This "scan cycle" repeats dozens of times a second, giving near-instant, predictable control.
- 1Read inputs — Check every connected switch and sensor
- 2Execute logic — Run the stored rules (ladder / function block)
- 3Update outputs — Energise or de-energise lights, relays, valves
A rule, drawn as a rung
PLC logic is usually written in "ladder" form — so called because each rule looks like a rung of a ladder between two power rails. On a rung, contacts in series mean AND, contacts in parallel mean OR, and the bracket ( ) at the end is the output that energises when the rung is true.
- Rung 1: the light comes on only when the switch AND the sensor are both closed
- Rung 2: a timer (TON) holds the pump on for 10 seconds after the trigger
- The same idea scales to heating zones, fire interlocks and security scenes
When a PLC makes Sense
An app hub is perfect for everyday "if this then that" scenes. A PLC is chosen when control must be deterministic and survives a network outage — think fire-misting interlocks, heating plant sequencing, smoke ventilation, or a large multi-unit development. Both can coexist: the PLC handles the safety-critical plant, while a hub exposes it to your phone for everyday convenience.
Backbones & Protocols
Different ways your devices talk to each other — we specify the right one for your home, budget and existing wiring.
PLC (Power Line Communication)
Control signals sent over your existing mains wiring — no new data cables required. PLC devices modulate a high-frequency carrier onto the power line, letting switches, sensors and appliances talk to each other through the same cables that power them.
- Uses existing mains wiring — no extra cable runs
- Robust, secure and not reliant on Wi-Fi coverage
- Ideal for retrofits and extensions into older homes
Wireless (Wi-Fi / Mesh)
Smart devices connect directly to your home network. Simple to install and app-controlled, but depends on reliable wireless coverage — a mesh system extends reach across larger homes.
- Easy retrofit, no central controller required
- Wide device choice and consumer-friendly apps
- Best for smaller homes or add-on rooms
Wired Bus Systems (KNX)
A dedicated low-voltage bus cable links every device to a central controller. The gold standard for new builds and full renovations — extremely reliable, scalable and interoperable across brands.
- Hard-wired backbone for maximum reliability
- Vendor-neutral open standard (KNX)
- Scales to whole-home and multi-unit projects
Hub & App Integration
Whichever backbone you choose, a central hub (or cloud platform) unifies devices and exposes them through a single app — letting you monitor and control everything from one screen, anywhere.
- One app for lighting, heat, security and energy
- Voice control via Alexa, Google or HomeKit
- Automations, schedules and remote alerts
Power Line Communication in plain English
PLC devices turn your home's existing mains wiring into a data network. A module plugged or wired in at one point superimposes a high-frequency signal onto the live conductor; a matching module elsewhere picks it up. That means a light switch can talk to a relay at the fitting, or a sensor can report to a controller — all without running new data cables. It's especially powerful for extensions and renovations into older Hampshire properties where lifting floors and chasing walls for cable would be disruptive.
Add smart controls to your build
We design and install smart home systems as part of your extension or renovation — wired, wireless or PLC, specified to suit your home.
Fire Misting Systems
Water-mist fire suppression is a modern residential alternative to traditional sprinklers. A fine mist cools the flame, displaces oxygen and suppresses re-ignition using a fraction of the water — protecting life and property without flooding the home.
Minimal Water Use
Uses around 90% less water than traditional sprinklers — a small tank protects a whole dwelling.
Life Safety
Suppresses fires in seconds, holding temperatures down and giving occupants time to escape.
Low Water Damage
Fine mist limits secondary water damage compared to a full sprinkler discharge.
Compact & Discreet
Small-bore pipework and concealed nozzles suit retrofit extensions and heritage homes.
How It Works
A sealed detection network monitors each room. On heat or smoke activation the pump pressurises the small-bore pipework and the nearest nozzle discharges a fine water mist at high pressure (typically 60–200 bar in high-pressure systems, or a low-pressure variant).
- Mist droplets (~100–300 µm) evaporate rapidly, absorbing heat from the flame
- Steam expansion displaces oxygen around the fire (local oxygen reduction)
- Only activated nozzles discharge — the rest of the home stays dry
- Operation linked to the fire alarm; optional monitoring / shutoff
- Typical discharge duration: 10–30 minutes from a residential tank
Typical Equipment Location
Per dwelling — indicative
Building Regulations
- Approved Document B (Fire Safety): fire suppression may be used to meet means-of-escape and compartment provisions, especially in open-plan layouts and where upper-floor escape distances are extended.
- BS 9251: Sprinkler systems for domestic and residential occupancies — code of practice for design, installation and maintenance.
- BS 8458: Fixed fire protection systems — residential and domestic watermist systems; the dedicated standard for water-mist in homes.
- Part B travel distances: a misting / sprinkler system can permit longer escape routes and open-plan ground floors.
- Water supply: the residential tank must provide the design discharge duration; cold-water feed and minimum pressure/flow verified.
- Third-party certification: installers should be LPS 1048 / BSI / IFCC certified; system commissioned and certificated on completion.
- Notification: a fixed suppression system is 'building work' for Building Regulations and must be notified to local authority control.
Technical Summary
Figures are indicative of high-pressure residential water-mist systems. Actual design is project-specific and must be verified by a qualified fire-safety engineer against BS 8458.
Protect what mattersFire misting can be designed into your extension from the outset — ask us how it fits your layout, budget and Building Regulations compliance.
Home Security Systems
Security works in layers — deter, detect, delay and respond. We design and install integrated systems covering alarms, cameras, sensors and remote access, planned around how your home is actually used.
Alarm System Layout
CCTV Coverage Plan
Smart Lock Access Flow
Intruder Alarms
Wired or wireless control panels that monitor door/window contacts and PIR sensors, triggering internal and external sirens on breach. Professionally graded to EN 50131 (Grade 2–3) for insurance recognition.
- Control panel + keypad
- Internal & external sirens
- EN 50131 grading
- Optional monitoring
CCTV & Video
IP cameras with night vision and motion-triggered recording, linked to an NVR or cloud storage. Coverage planned to eliminate blind spots at entries, driveways and rear access.
- 4K / 2MP IP cameras
- Night vision & ANPR
- NVR or cloud storage
- Mobile live-view
Sensors & Detection
Magnetic contacts on openings, PIR motion detectors, glass-break and vibration sensors, plus environmental sensors for smoke, heat, CO and flood. The first layer of any layered defence.
- Door/window contacts
- PIR & dual-tech motion
- Glass-break & vibration
- Smoke, CO & flood
Remote Locks & Access
Smart deadbolts and electronic gate releases operated by app, keypad, fob or biometric. Grant time-limited codes to trades or guests and log every entry — no keys to lose or copy.
- App / keypad / fob
- Time-limited codes
- Entry logging
- Gate & door release
Perimeter & Lighting
Beam sensors, driveway alarms and PIR-activated security lighting that deter and detect before an intruder reaches the building. Often the most cost-effective layer.
- Active infrared beams
- PIR floodlighting
- Driveway alerts
- Deter + detect
Monitoring & Response
Optional 24/7 alarm and video monitoring via an Alarm Receiving Centre (ARC), with keyholder alerts and, where appropriate, police URN response for confirmed activations.
- 24/7 ARC monitoring
- Keyholder alerts
- Police URN response
- Cloud video verification
Plan your security early
Cabling and sensors are cheapest to install during a build or extension. We'll design the system with your project — not retrofit it after.
Rainwater Harvesting Systems
A well-designed rainwater system can cut mains water use for toilets, laundry and gardens by up to 50%. We size the collection, filtration, storage and pumping for your roof and demand — built to comply with Building Regs Part G and HWR recommendations.
System Layout
Filtration Cascade
Pump & Controls
Collection & Gutters
Rainwater is captured from the roof via gutters and downpipes. Roof type, pitch and orientation determine yield — a 100 m² roof in Hampshire collects roughly 55,000 L per year. We size gutters and diverters to handle storm peaks without overflow.
- Roof area yield calc
- Oversized gutters
- First-flush diverter
- Leaf screens
Filtration Stages
Water passes through a cascade of filters before storage: a coarse leaf filter at the downpipe, a fine mesh stainless filter at tank entry, and a calming inlet inside the tank. For potable reuse a UV steriliser polishes the supply at point of use.
- Coarse leaf filter
- Fine stainless mesh
- Calming inlet
- Optional UV unit
Storage Tank
Underground GRP or polyethylene tanks sized to typical dry-spell demand — usually 1,500–6,500 L for a home. Kept dark and cool to suppress algae, with an overflow that discharges to a soakaway and a floating suction intake drawing the cleanest water.
- 1,500–6,500 L sizing
- Dark, cool storage
- Floating suction
- Soakaway overflow
Pump & Pressure
A submersible multistage pump (or in-house booster set) delivers mains-equivalent pressure to WCs, washing machines and outside taps. Pressure is held by a small accumulator so the pump doesn't cycle for every flush.
- Submersible multistage
- Accumulator tank
- Pressure switch
- Dry-run protection
Controls & Top-up
A control panel monitors tank level via float switches. When rainwater runs low, a solenoid opens a mains top-up (via a type-A air-gap — no cross-contamination) to keep supply running, then switches back automatically when it rains.
- Level float switches
- Type-A air-gap top-up
- Auto mains backup
- Level display
Outlets & Usage
Treated rainwater feeds WCs, washing machines, garden taps and (with UV) drinking water — each on a dedicated, clearly-labelled pipework run kept separate from the mains by a dual-network manifold and colour-coded pipework.
- WCs & laundry
- Garden & irrigation
- Dual-network pipework
- Colour-coded runs
Add water recycling to your build
Tanks and dual-network pipework are far cheaper to install during construction than to retrofit. We'll design the system with your project from day one.
Not sure which system fits?
Book a free consultation and we'll recommend the right method for your home.
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