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DJ COX BUILDING SERVICES LTD: plumbing, heating and air-conditioning company in Welwyn
DJ COX BUILDING SERVICES LTD is an active limited company (no. 12240065), incorporated in 2019, registered for plumbing, heating and air-conditioning installation (SIC 43220), with its registered office in AL6 (Welwyn), and 276 similar companies have a registered office within 10 km. If you need an MCS-certified air-to-air installer, MCS lists 0 installers certified for air-to-air heat pumps yet (checked 25 Sep 2026), so no company here can offer the £2,500 grant route today.
Active
Within 10 km
276 similar companies within 10 km. Welwyn
What homes around AL6 need
In AL6 last summer (2026) there were ≈11 nights that stayed above 18 °C — 7 times the 1991–2020 average of 1.5 (ERA5 reanalysis, grid ≈30 km, lower than street temperatures in cities).
10% of sampled postcodes in AL6 sit in a conservation area (on-record, 506 live postcodes).
In England an air-source heat pump on a house can be permitted development under Class G when the conditions hold, including the MCS 020a noise limit of 37.0 dB(A) (§3.2 Step 8).
Hot nights: ERA5-ARCO, June–August, minimum at or above 18 °C, 2026 against the 1991–2020 mean, retrieved 25 Sep 2026. Conservation-area share: sampled postcode points, snapshot 25 Sep 2026. Noise limit from the decision contract, checked 25 Sep 2026.
Nearest similar companies
| Company | Number | District | Distance |
|---|---|---|---|
| WARMSPARK BUILDING SERVICES LTD | 14976829 | AL7 | ≈0.8 km |
| SAS PLUMBING HEATING & ELECTRICAL LTD | 12051417 | AL8 | ≈0.9 km |
| D E&P LIMITED | 16002805 | AL8 | ≈1.1 km |
| AL8 PLUMBING LTD | 17404439 | AL8 | ≈1.1 km |
| FLODOC LTD | 16634087 | AL7 | ≈1.1 km |
| TOTALFIX MAINTENANCE LTD | 16851162 | AL8 | ≈1.2 km |
| PRO VENTILATION LTD | 10325193 | AL8 | ≈1.2 km |
| LT AIR CONDITIONING LIMITED | 17167351 | AL8 | ≈1.2 km |
| C A WARNER LTD | 09931611 | AL6 | ≈1.4 km |
| SEHITI PLUMBING AND HEATING LTD | 17165985 | AL6 | ≈1.4 km |
Company record
| Field | Value |
|---|---|
| Company number | 12240065 |
| Name | DJ COX BUILDING SERVICES LTD |
| Status | Active |
| Incorporated | 2 Oct 2019 |
| SIC | 43220 · plumbing, heat and air-conditioning installation; 43210 · electrical installation; 41202; 43910 |
| Registered office postcode | AL6 0DR |
| Outcode | AL6 |
| Nation | England |
| Air-to-air signal | not yet observed, checked 25 Sep 2026 |
| F-Gas | not yet observed, checked 25 Sep 2026 |
| MCS air-to-air | not yet observed, checked 25 Sep 2026 |
| Retrieved | 25 Sep 2026 |
| Dataset | https://download.companieshouse.gov.uk/BasicCompanyDataAsOneFile-2026-09-01.zip |
| Companies House page | Company 12240065 |
Companies House record: DJ COX BUILDING SERVICES LTD, company 12240065, status Active, retrieved 25 Sep 2026. The address shown is the registered office, not a verified operating base. This catalogue is a directory of incorporated businesses, not an exhaustive installer register. Snapshot 1 Sep 2026, retrieved 25 Sep 2026. The 10 km count is equirectangular to 0.1 km. MCS air-to-air confirmed in this catalogue: 0, checked 25 Sep 2026.
Better than a reviews catalogue: the Companies House record, the district hot-night count and the MCS air-to-air observation are on one page.