You likely will require advertisement consent to display a commercial advertisement outside your home, especially when the company does not operate from that location.

 It is more likely that permission will be required where:

• the sign is over 0.3 square metres or illuminated
• the sign is visible from a road
• the building is listed or in a designated area then consent

Find out more about advertisement consent on Planning Portal.

Yes, under permitted development, a new dormer must not be higher than the existing highest part of the roof. It should also have materials that are in similar appearance to the existing roof. Additional limits apply in conservation areas and on listed buildings. Read about planning permission for loft conversions on Planning Portal

By law, any planning permission granted expires after a certain period. Generally, unless your permission says otherwise, you have three years from the date it's granted to begin the development. If you haven't started work by then, you will probably need to reapply.

Running a taxi business from home will require planning permission as it constitutes a change of use of the property. The business may cause increased traffic or visitors, staff being in the property and external advertising, all of which would have an impact on the surrounding area.

You should contact your local planning authority or the Planning Guidance Service for more advice.

Removing a chimney stack may fall under permitted development rights, meaning no application for planning permission is required provided certain limits and conditions are met.

The permitted development right which covers this focuses on the installation, alteration or replacement of a chimney, note that this does not specifically mention removal. Rules in a conservation area may differ, in this instance you should contact your local planning authority directly to understand their position, and if the building is listed, then you will need listed building consent.

To ensure that the local planning authority will allow the removal of the chimney stack you can apply for a lawful development certificate. If approved, then no enforcement action can be taken against the change.

If the chimney is shared (i.e. as part of a terrace), you might need to discuss with relevant neighbour and obtain a party wall agreement.

Building regulations approval may not be required if you are removing the external chimney stack above the roof. If works progress to the internal chimney stack or breasts, then it will require building regulations to understand the structural impact.

Read more about planning and building regulations on Planning Portal.