Roseland · TR2 · Cornwall Council Mid
Passivhaus architect in St Mawes — low-energy homes done properly
Passivhaus in St Mawes is not a marketing sticker — it's a numbers-driven design method that requires orientation modelling, air-tightness planning and MVHR sizing from the first sketch. On coastal plots in TR2, the wind exposure is the first variable we test in PHPP. A bespoke new build is the longest project we do, and the most rewarding. From plot appraisal through planning, building regulations and construction, you work with one team from the first sketch to the handover walk-round. On a St Mawes site, the brief always meets the place — St Mawes sits on the Roseland Peninsula opposite Falmouth across the Carrick Roads, with a Henrician castle, ferry harbour and one of the highest property value markets in Cornwall, with a building stock that leans toward Georgian seafront houses and modern architect-designed coastal homes.
St Mawes sits in Roseland — just off the A3078; covering TR2 from St Just in Roseland, Portscatho, Gerrans outward.
- Conservation Area
- Cornwall AONB
- Coastal exposure zone
- Rural / open-countryside policy area
- ✓Full PHPP modelling available
- ✓MVHR sizing and air-tightness planning
- ✓8–15% build premium, ~zero running cost
- ✓Cost: £3,600–£4,800/m² built
Free · No obligation
Free St Mawes feasibility call
Tell us about your new build. We reply within 1 working day — no obligation.
Who this is for
In St Mawes the new build brief is almost always a private homeowner improving a forever home — so we lead with feasibility and long-term value, not show-home rhetoric.
Local watch-list
Local snags worth knowing before drawing a St Mawes new build.
Watch #1
Conservation Area controls on materials, window proportions and roof form through central St Mawes
Watch #2
AONB landscape-impact testing on anything read in long views across Roseland
Watch #3
Exposure detailing on Georgian seafront houses — fixings, render systems and joinery specified for salt-laden air
Watch #4
Local Plan tests on isolated dwellings, plus lane access for plant and deliveries around St Mawes
Local proof — Our Roseland workload means a St Mawes new build project never has to wait for an out-of-county team to drive down.
Get a free feasibility viewFAQs
St Mawes New Builds — local questions answered.
- Is Passivhaus worth it in St Mawes?
- Financially, the 8–15% build premium pays back in 15–20 years at current energy prices. Comfort-wise, the payback is immediate. On new-builds in TR2, we recommend it on any plot with reasonable orientation.
- Do you produce full PHPP models?
- Yes, or we work alongside a certified PHPP consultant. Either route lands the same result — a fully modelled, air-tightness-tested certified Passivhaus.
- What's the cost difference vs a standard new build?
- £3,600–£4,800/m² for Passivhaus vs £3,000–£4,000/m² for a well-insulated standard build. Premium is smaller than most people expect.
- We live in the house. Can a new build in St Mawes be done while we stay put?
- Usually yes for single-storey and rear work, with a temporary kitchen or bathroom arrangement agreed before the start. Whole-house remodels and roof work in St Mawes are often easier if you move out for a few weeks. We set that expectation at feasibility stage rather than halfway through.
- How much does a new build cost?
- Realistic budgets in Cornwall start around £2,800 per square metre for a good-quality build and rise quickly with bespoke joinery, large glazing, complex sites and high-spec finishes. We work to your number, not against it. In St Mawes specifically, we'd start by checking the Conservation Area boundary before committing to a direction.
- Can you handle a self-build for me?
- Yes — from feasibility to handover. Many of our clients start as 'self-builders' on paper, then hand the actual build to us once they realise how much project management it takes.
Quick check
Want a straight answer on whether your St Mawes project is worth pursuing?
Send a few details — we'll come back within 1 working day with a plain-English view on planning risk, likely cost band and whether it's a project we'd take on.
Free · No obligation
Get a free feasibility view
For projects in St Mawes and the TR2 area.
Who this is for
Why this page exists, and who it is for
- Drawings, planning and building regulations are all produced in-house, so a new build enquiry does not get passed between firms.
- Designated-area work is routine here, so heritage and landscape statements are produced alongside the drawings rather than outsourced.
- Applications for St Mawes are handled through Cornwall Council, with St Austell the nearest planning office we deal with regularly.
Planning rules change and every site is different. For the final position on your address, check with Cornwall Council as the local planning authority or the Planning Portal.
Keep reading
Follow the chain: survey, drawings, build
We cover St Mawes and the wider TR2 district directly. New Builds enquiries here are common enough that we know the constraints before the first visit.
Page purpose
Drawings only, or drawings through to handover in St Mawes?
Both routes are open on a TR2 project, and the honest answer depends on whether you already have a builder you trust. Plenty of St Mawes clients take the drawings, tender them locally, then come back to us for the build if the numbers do not stack up.
- Route one: feasibility, planning and a tender-ready technical pack
- Route two: the same pack, then the build under one contract
- Either way the survey and feasibility work is identical, so the decision can wait
- Fees quoted per stage against the TR2 scope, not as one opaque figure
Scope
What we can draw, survey and build around St Mawes
Clients in St Mawes take different slices of this list, and that is deliberate.
Heritage and design statements
Written justification where designation makes the design case as important as the drawing.
Building regulation drawings
Full Plans sets with sections, construction notes and coordinated structural information.
Structural coordination
Calculations coordinated with the drawings so building control sees one consistent story.
Planning application drawings
Existing and proposed plans, elevations, site and block plans drawn to validation standard.
Full design and build
One contract from first sketch to handover, with the same team on paper and on site.
Local context
Why St Mawes is its own job.
The planning backdrop in Roseland is real, not abstract: conservation Area covers the seafront and harbour; AONB and Heritage Coast across the peninsula. Tight policy resistance to second-home expansion in some Roseland parishes. For new build specifically, parts of St Mawes sit within a designated Conservation Area, which means materials, fenestration and roof pitches all need to read sympathetically with the existing streetscape; the surrounding landscape falls inside the Cornwall Area of Outstanding Natural Beauty, so massing, height and landscape impact carry extra weight in any planning decision; coastal salt-laden air around St Mawes drives detailing choices — fixings, render systems and timber treatments all need to be specified for exposure; Cornwall Council's Local Plan applies tighter tests to isolated rural dwellings here, so design rationale and policy fit need to be set out clearly from the outset. Treat the TR2 parish brief as the design brief and the St Mawes application has somewhere to land. Whether the project is on Georgian seafront houses in the centre or further out toward Philleigh, the new build response is locally tuned. On older stock, the practical constraint is usually joinery, render and roof line rather than the extension itself. We draw those details out early so a new build submission is not sent back for missing information. Confirm listing status with the local planning authority before assuming permitted development. Salt air and prevailing wind change specification long before they change planning. We tend to draw weathering details in full, then check whether coastal or AONB policy narrows the design options for this address.
Planning note
Cornwall's planning policy on new dwellings is among the most restrictive in England outside Greater London. The first conversation should be a planning conversation, not a design one.
What we focus on
New Builds considerations specific to St Mawes.
01
Off-grid services — package treatment plants, borehole supply, off-mains gas — are common on rural Cornish plots and need designing, not assuming.
02
Cornwall's housing policy increasingly favours principal residence and replacement dwelling schemes over open-market new builds in some parishes.
03
AONB and Heritage Coast designations apply to large stretches of the county; isolated new builds outside settlement boundaries face a much higher policy bar.
04
Replacement dwellings have specific volumetric tests — getting the ratio between existing footprint and proposed floor area right is the difference between approval and refusal.
Our process
How a St Mawes new build project runs.
Step 1
Plot review
Site visit, planning history check, designation review and an honest feasibility verdict.
Step 2
Concept design
Sketches that test the plot in massing, orientation and approach before any drawings are committed.
Step 3
Planning
Pre-app, full planning, consultee management and condition discharge.
Step 4
Technical design and build prep
Building regs, structural design, services strategy and contractor procurement.
Step 5
Construction and handover
Build delivered under contract administration with regular client reviews.
Most bespoke new builds run eighteen to thirty months from instruction to keys, depending on site, planning route and build complexity.
Local fabric
Why a Roseland studio is the right fit for St Mawes new build.
Building stock
Across St Mawes (TR2) we work on Georgian seafront houses, Victorian villas, Edwardian villas above the harbour, modern architect-designed coastal homes. Each stock type drives a different new build response — Georgian seafront houses in particular needs careful detailing here.
Parish & policy
St Mawes is its own town in Roseland, with planning history that's specific to the TR2 catchment.
Coverage
We cover TR2 from our studio, with regular new build jobs also running in Ruan Lanihorne. Most St Mawes site visits get booked within the same week.
What does a first St Mawes consultation cost?
Nothing. We come to the property, walk the site, talk through what works on a TR2 plot and follow up with a written feasibility note inside a week — no obligation either way.
Request a free visitOther services in St Mawes
Nearby places we cover
A St Mawes Passivhaus costs 8–15% more to build and roughly nothing to run — the payback is in comfort as much as bills, and the resale market for certified homes is strengthening year on year.
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