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Arch+

Also seen as: Grey Bear Chartered Architect
www.arch-plus.co.uk

Chartered architecture practice (trading name "Grey Bear") specialising in accessible/inclusive design, 17+ years in all building sectors; models every project in 3D for client walkthroughs. Not RICS-regulated. 40 applications as agent 2022-2025.

We are a chartered architecture practice based in Guernsey, Channel Islands. High quality architecture and inclusive design is at the heart of Arch+.

Arch+’s own words, from www.arch-plus.co.uk . Quoted as published — this site neither vets nor endorses any firm.

Images published by Arch+ on their own website.

What they specialise in

Work types this firm files more often than the island does — "×3.9" means nearly four times the rate that type appears across all Guernsey applications. Ordered by the value of the work, not the ratio, so the jobs that actually pay come first: a rebuild at ×1.7 is worth far more than window replacement at ×2.5.

Work typeVs island rateJobsTypical jobEst. value of this work
Single-storey extension×1.917£100,000£1,700,000

"Est. value of this work" is the typical job cost for that type multiplied by how many they filed — a rough sense of where the practice's money sits, not their fees or their turnover. Needs at least 12 applications on file and 3 in the category before a ratio is shown, so a small practice can't look like a specialist on two lucky jobs. Classified from each application's own wording, so a minority will sit in a category a human would read differently.

The properties they work on

Of 40 applications this firm filed, 14 are tied to a later recorded sale of the same address, and 12 of those carry a real price. The midpoint is £944,690, each carried forward to 2026 money at the island index. Most of their filed work is in St Peter Port (9), St Martin (8), Vale (6).

1 matched sale recorded at a nominal £1–£100 was excluded — those are family or trust transfers, not market prices. Matching is by address and parish against the States register, not a shared ID, so a shared house name can mismatch. It tells you the value bracket this firm operates in; it is not their fee and not a claim about any individual job.

Work-type mix

Classified from each application's own description text, most common first — the same keyword model this site's planning cost estimates use. Select a type to filter the applications below.

Typical cost of work

£35,132–£63,487 average, estimated per application from its own description text using this site's planning cost model — a rough guide only, not a quote from Arch+ or a reflection of what any specific job actually cost, and it does not include design fees. Each row below also carries an estimate at the prices of the year it was filed, deflated with the island house-price index — a proxy, since that index tracks house prices rather than construction costs and the two genuinely diverge (materials spiked in 2021–22 well beyond house-price growth). No Guernsey construction-cost index is published, so this is the best basis available, and it is an estimate on top of an estimate. 2 demolish-and-rebuild applications excluded from the average — that category prices per m² of the rebuild, which isn't recorded per application here.

40 planning applications as agent — real cross-references

Success rate on decided applications: 92% granted (36 granted, 3 refused, of 39 decided — pending/withdrawn excluded)

ApplicationAddressDescriptionDecision
FULL/2023/1406Les Brehauts Farmhouse Route Du Longfrie St. Pierre Du Bois Guernsey GY7 9RXChange of use of 3 self-catering units (Visitor economy Use Class 8) to 3 dwellings with associated works (Res…
Est. £17,610–£46,960 at 2023 prices
RefusedFull record
Decision notice (PDF)
FULL/2023/1568Slipway at Pembroke La Jaonneuse Road Vale GuernseyDemolish existing shed and erect single storey building/store.
Est. £9,392–£21,132 at 2023 prices
GrantedFull record
Decision notice (PDF)
FULL/2023/1597Malusha & Beauvais House Avenue Vivier Ville Au Roi St. Peter Port Guernsey GY1 1PGExtend, alter and convert 2 dwellings to create 5 flats including raise and alter roof, and erect dwelling to …
Est. £14,088–£29,350 at 2023 prices
WithdrawnFull record
FULL/2023/1696Atlantis Bouillon Lane St. Peter Port Guernsey GY1 2BFRemove section of roadside wall to create vehicle access and parking area to south-west (roadside) boundary.
Est. £5,870–£17,610 at 2023 prices
GrantedFull record
Decision notice (PDF)
FULL/2023/1761Die Insel Les Petites Mielles St. Sampson GuernseyDemolish glasshouse and erect outbuilding to north-east boundary.
Est. £29,350–£52,830 at 2023 prices
GrantedFull record
Decision notice (PDF)
FULL/2023/1776Rochdale Clos Des Covins Rue Des Cauvains Castel Guernsey GY5 7NRAlter roof form of extension to south (side) elevation and install replacement windows.
Est. £52,830–£88,050 at 2023 prices
GrantedFull record
Decision notice (PDF)
FULL/2023/199779 The Citadel Hautes Falaises Fort George St. Peter Port Guernsey GY1 2SXVariation to previously approved plans to extend at lower ground and ground floor level, install dormer window…
Est. £52,830–£76,310 at 2023 prices
GrantedFull record
Decision notice (PDF)
FULL/2023/2347Edenbridge 5 Route De La Croix Au Bailiff St. Andrew Guernsey GY6 8RTErect single storey extension to north-east (rear) elevation and alterations to fenestration.
Est. £52,830–£88,050 at 2023 prices
GrantedFull record
Decision notice (PDF)
FULL/2023/2367Land Adjacent To Coniston La Grande Rue St. Martin Guernsey GY4 6RTErect 3 dwellings with associated works and create new vehicle access to north-east boundary.
Est. £5,870–£17,610 at 2023 prices
GrantedFull record
Decision notice (PDF)
FULL/2023/2414Vue Du Vallon Le Varclin St. Martin Guernsey GY4 6APRaise roof ridge height and create first floor level accommodation, extend and alter at ground floor level.
Est. £14,088–£29,350 at 2023 prices
GrantedFull record
Decision notice (PDF)
FULL/2023/2454Tigh-Na-Craig Rue Du Pont Vaillant Vale Guernsey GY6 8BUErect 1.5 storey pitched roof and single storey flat roof extension to north-east and south-east (side) elevat…
Est. £52,830–£88,050 at 2023 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/0049Maison Des Effards Les Effards Road St. Sampson Guernsey GY2 4YWConvert art studio to dwelling with associated works and remove section of wall to widen vehicle access.
Est. £6,096–£18,288 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/0144Trafalgar Court Les Banques St. Peter Port Guernsey GY1 3EZInstall benches, picnic table, table tennis table and ornamental feature to existing hardstanding area.
Est. £18,288–£48,767 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/0187Marlin Sous Les Courtils Castel Guernsey GY5 7HSErect single storey flat roof double garage to north boundary.
Est. £30,479–£54,863 at 2024 prices
Granted
Later sold 2023-04-20 · £589,875
Full record
Decision notice (PDF)
FULL/2024/0350Woodstock Oatlands Lane St. Sampson Guernsey GY2 4FDDemolish extension, erect 1.5 storey extension to south (rear) elevation, install dormer windows and rooflight…
Est. £54,863–£91,438 at 2024 prices
Granted
Later sold 2025-07-10 · £653,250
Full record
Decision notice (PDF)
FULL/2024/0352Le Manoir De Sous L'Eglise Rue De Sous L'Eglise St. Saviour Guernsey GY7 9TQDemolish existing conservatory/link extension, erect single storey extension with terrace at 1st floor level t…
Est. £54,863–£91,438 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/0387Les Mouissaons Mont Arrive St. Peter Port Guernsey GY1 2AAInstall window at first floor level to south (side) elevation and alterations to fenestration.
Est. £18,288–£48,767 at 2024 prices
Granted
Later sold 2021-01-14 · £755,625
Full record
Decision notice (PDF)
FULL/2024/0404Charmaine Jerbourg Road St. Martin Guernsey GY4 6BGVariation to previously approved plans to demolish dwelling and outbuildings, erect new dwelling and widen exi…Granted
Later sold 2015-10-29 · £345,000
Full record
Decision notice (PDF)
FULL/2024/0543Ranui 13 Meadow Drive Ruette Du Villocq Castel Guernsey GY5 7SJDemolish conservatory, erect 2 storey extension to south (rear) elevation and alterations to fenestration.
Est. £54,863–£91,438 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/0641Edenbridge Route De La Croix Au Bailiff St. Andrew Guernsey GY6 8RTVariation to previously approved plans to erect single storey extension to north-east (rear) elevation and alt…
Est. £54,863–£91,438 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/0734The Haven La Moye Road Vale Guernsey GY3 5DRDemolish section of roadside wall to widen vehicle access and alter hardstanding to north of property.
Est. £6,096–£18,288 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/0834Vue de la Tour Rue De L'Issue St. Pierre Du Bois Guernsey GY7 9HTDemolish chimney and dormer windows. Erect 2 storey extension, dormer window and porch to north-west (front) e…
Est. £54,863–£91,438 at 2024 prices
Granted
Later sold 2023-08-24 · £887,250
Full record
Decision notice (PDF)
FULL/2024/0966The Cottage L'Hyvreuse Avenue St. Peter Port Guernsey GY1 1UZRaise roof height, remove garage door and infill, alterations to fenestration of extension to north (front) el…
Est. £54,863–£91,438 at 2024 prices
Granted
Later sold 2021-07-08 · £736,125
Full record
Decision notice (PDF)
FULL/2024/1079Akaroa Rue Des Corneilles Castel Guernsey GY5 7PPDemolish extensions, raise and alter roof ridge height to create accommodation at 1st floor level, extend and …
Est. £54,863–£91,438 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/1153Awali Val Au Bourg St. Martin Guernsey GY4 6EPVariation to previously approved plans to raise and alter roof height to create 1st floor accommodation, exten…
Est. £30,479–£54,863 at 2024 prices
Granted
Later sold 2020-07-16 · £1,511,250
Full record
Decision notice (PDF)
FULL/2024/1156The Haven La Moye Road Vale Guernsey GY3 5DRDemolish extension, outbuildings, erect single storey extension to south (rear) elevation, install rooflights …
Est. £54,863–£91,438 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/1341Les Mouissaons Mont Arrive St. Peter Port Guernsey GY1 2AAInstallation of external render to north, south, east and west elevations.
Est. £18,288–£48,767 at 2024 prices
Granted
Later sold 2021-01-14 · £755,625
Full record
Decision notice (PDF)
FULL/2024/1591Sundowner Rue Du Pont Vaillant St. Peter Port Guernsey GY1 2UQErect balcony at first floor level to east (rear) elevation.
Est. £18,288–£48,767 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/1892Les Tilleuls St. Jacques St. Peter Port Guernsey GY1 1SPDemolish extensions, extend and alter at ground floor and 1st floor levels including 1st floor terrace area to…
Est. £54,863–£91,438 at 2024 prices
Granted
Later sold 2023-09-28
Full record
Decision notice (PDF)
FULL/2024/1901Petite Lande Rue Des Monts Forest Guernsey GY8 0BBConvert, extend and alter building to create dwelling and associated works. Change of use of agricultural land…
Est. £18,288–£48,767 at 2024 prices
Refused
Later sold 2023-07-27 · £1
Full record
Decision notice (PDF)
FULL/2024/1910Mouilliere Le Mont Durand St. Martin Guernsey GY4 6DJErect porch to east (front) elevation and bike store to south (side) elevation and alterations to fenestration…
Est. £7,315–£14,630 at 2024 prices
Granted
Later sold 2022-02-01 · £1,340,625
Full record
Decision notice (PDF)
FULL/2024/1933Croix du Lorier Le Chene Forest Guernsey GY8 0AJDemolish extension, erect single storey extension to west (rear) elevation and erect dormer window to south (s…
Est. £54,863–£91,438 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/1944Cortijo Bravo Les Vaurioufs St. Martin Guernsey GY4 6SZDemolish extension, erect 2 storey and single storey extensions to east (rear) elevation and alterations to fe…
Est. £54,863–£91,438 at 2024 prices
Granted
Later sold 2015-01-22 · £669,750
Full record
Decision notice (PDF)
FULL/2024/1953Brise de Mer Rue Du Camp Du Douit St. Saviour Guernsey GY7 9QWDemolish extension, erect single storey extensions to north (side) and south (side) elevations, install dormer…
Est. £54,863–£91,438 at 2024 prices
GrantedFull record
Decision notice (PDF)
FULL/2024/2007La Petite Hure Val Au Bourg St. Martin Guernsey GY4 6EPRemove section of earth bank to widen vehicle access and erect gates to west (roadside) boundary.
Est. £6,096–£18,288 at 2024 prices
Granted
Later sold 2013-11-28 · £836,000
Full record
Decision notice (PDF)
FULL/2025/0053La Petite Hure Val au Bourg St. Martin Guernsey GY4 6EPErect single storey extension with raised terrace area and rooflight to south (rear) elevation, erect single s…
Est. £56,694–£94,489 at 2025 prices
Granted
Later sold 2013-11-28 · £836,000
Full record
Decision notice (PDF)
FULL/2025/0303By The Sea Les Prins Lane Portinfer Road Vale Guernsey GY6 8HHDemolish summerhouse, erect outbuilding/summerhouse to north-east boundary.
Est. £31,496–£56,694 at 2025 prices
GrantedFull record
Decision notice (PDF)
FULL/2025/0322Le Petit Champ Ruette De La Croix Castel Guernsey GY5 7NWDemolish extensions, outbuilding and glasshouse. Extend and alter dwelling at ground and first floor level, er…GrantedFull record
Decision notice (PDF)
FULL/2025/0324Laarbruch La Rochelle Road Vale Guernsey GY3 5DYDemolish section of wall to create vehicle access and parking to south west (front) of property.
Est. £6,299–£18,898 at 2025 prices
RefusedFull record
Decision notice (PDF)
FULL/2025/0372Akaroa Rue Des Corneilles Castel Guernsey GY5 7BPErect single storey flat roof extension and install rooflight to east (rear) elevation, install canopy to west…
Est. £56,694–£94,489 at 2025 prices
GrantedFull record
Decision notice (PDF)
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