Build a home for family in your garden in Hatfield

If you have a long or wide garden in Hatfield, there may be room for a home where a parent or grown-up child can live close by with their own front door. That might mean an annexe used with your house, or a home that stands alone with permission and paperwork of its own.

Welwyn Hatfield Borough Council decides either way, so the first step is to find out what your plot can realistically carry. Our free plot appraisal covers access, space, privacy and the main planning constraints, and talks through who the home is for, before you spend any money on drawings.

Single-storey garden home with wide glazed doors and a covered porch at the back of a family garden
Planning authority
Welwyn Hatfield Borough Council
Postcodes
AL9, AL10
Noon sun, 21 March
About 38°
Shadow from a 5 m eaves line
About 6.3 m
Planning plan
Local Plan
County
Hertfordshire

What shapes a plot in Hatfield

Welwyn Hatfield Borough Council will judge a family home against the council’s Local Plan and any guidance it has adopted on garden development and annexes. Some councils spell out how closely an annexe must relate to the main house, such as sharing the drive, garden or parking, and what turns a building into a separate home instead. We read the current policies for your address before design starts, because a scheme drawn to suit the wrong test wastes time and money. Where the position is unclear, the council’s pre-application advice can be worth its fee.

Section showing noon sun and shadows in Hatfield: about 38 degrees on 21 March and 15 degrees on 21 December21 m21 Mar, noon: sun 38°, shadow 6.3 m21 Dec, noon: sun 15°, shadow 18.9 mExistingNew home
Noon sun in Hatfield on 21 March sits about 38° above the horizon, so a typical two-storey eaves line (about 5 m) throws a shadow of roughly 6.3 m. In December the sun is only about 15° up and shadows stretch much further. Drawn for a garden facing north, where it matters most.

The next steps, locally

Here’s what happens next for a family home in Hatfield. You tell us about your plot and who the home is for, and we carry out a free desktop appraisal of access, space and the planning context. If it looks viable we visit, then set out the annexe and separate-home options. With your go-ahead we survey, design and give you a written quote, then prepare the application for Welwyn Hatfield Borough Council.

  1. Free plot appraisal

    We look at your plot, access and the planning picture from the desk, talk through who will live in the new home, and visit if it looks viable. There’s no cost and no obligation.

  2. Annexe or separate home

    We set out both routes for your plot, covering what each means for planning, ownership, council tax, CIL and VAT, so you can decide with your family and advisers before design starts.

  3. Planning and approvals

    We prepare and submit the planning application and manage it with the council, which makes the decision. Before work starts, approval under the Building Regulations is in place and any CIL exemption has been claimed.

  4. Build and handover

    We build while you carry on living next door, with access, deliveries and working hours agreed up front. At handover you get the completion certificate and the paperwork you’ll need for council tax, lenders and any VAT claim.

Worth checking early

  • Planning is the council’s decision, and an annexe is not a way round the rules that apply to a new house.
  • CIL exemptions are lost if work starts before the claim is made, and can be withdrawn if the home is sold or let within three years.
  • Family plans change: agree ownership, costs and what happens if circumstances change in writing, with a solicitor.

Hatfield: questions to ask

Will an annexe in Hatfield put up my council tax?

It might. Annexes can be banded separately, but exemptions exist for annexes lived in by certain dependent relatives, and in some cases a discount applies where family live there or the annexe is used as part of the main home. Who qualifies depends on the relative’s circumstances and how the annexe is used. Welwyn Hatfield Borough Council’s council tax team can tell you how the rules apply to your household.

Do I need planning permission for a granny annexe in Hatfield?

Yes, almost always for a detached annexe with its own kitchen, bathroom and bedroom. Welwyn Hatfield Borough Council will treat it as accommodation linked to your home and will usually add a condition so it can’t be let or sold separately. A garden building used only as a home office or gym is a different matter, but sleeping and cooking take it beyond those allowances.

Can I build a separate house in my Hatfield garden for my son or daughter?

Possibly, if the plot can work as a home in its own right. Welwyn Hatfield Borough Council will look at access, parking, garden space for both houses, privacy and the character of the street, as it would for any new house. If permission is granted, the plot can be transferred to your child with its own title, with your lender’s consent if the house is mortgaged.

How much garden do I need for a family home in Hatfield?

There’s no fixed figure. A single-storey annexe close to the house can work on a smaller plot than a separate dwelling, which needs its own garden, parking and access. What matters is whether Welwyn Hatfield Borough Council can be satisfied on privacy, daylight and the space left for both homes. The free appraisal gives you a first view based on your plot’s actual shape and access.

Other options in Hatfield

Family home in your garden near Hatfield

Find out what your garden could become

Free garden plot appraisal. No cost, no obligation, and a straight answer if it won’t work.