Single & Double Storey Extensions
- Single-storey, double-storey, rear and side extensions
- Bexleyheath-based builders covering Dartford and surrounding areas
- Extension work planned around your property, budget and living space
Friendly & Reliable
How single and double-storey extension projects are planned
The process starts with understanding what the extra space needs to achieve. A homeowner may want a bigger kitchen, a more comfortable family room, an additional bedroom, a downstairs WC, a utility area or better flow between the house and garden. TRM Innovations Ltd will look at the existing layout, access, garden space, neighbouring boundaries, drainage, roof position and how the new extension should connect with the rest of the property.
Once the aim is clear, the next stage is to consider drawings, structural requirements, planning permission, Building Regulations, foundations, steelwork, roofing, windows, doors, electrics, plumbing and internal finishes. A rear single-storey extension may be more straightforward than a two-storey extension, but both need careful planning so the finished build looks right and performs properly. Speak to TRM Innovations Ltd if you want a practical extension quote based on your home rather than a vague square-metre estimate.
Highly experienced
Extension builders for homes that need more usable space
A single-storey extension is often the right choice when you want a larger kitchen, open-plan dining area, utility room, garden-facing living space or ground-floor office. A double-storey extension can go further by adding space upstairs too, such as an extra bedroom, larger bathroom, dressing area or improved landing layout. TRM Innovations Ltd helps homeowners choose the option that suits the property rather than pushing one fixed idea.
Established in 2014, TRM Innovations Ltd is based in Bexleyheath and covers surrounding areas across Dartford, Welling, Sidcup, Bexley, Blackfen, Erith, Crayford and nearby parts of South East London and Kent. If you are comparing single storey extension builders, double storey extension builders or a local extension building company, contact TRM Innovations Ltd for clear advice and a free quote.
Where we operate
Local extension builders across Bexleyheath, Dartford and nearby areas
TRM Innovations Ltd works with homeowners across Bexleyheath, Dartford, Welling, Sidcup, Bexley, Blackfen, Erith, Crayford, Abbey Wood, Eltham, Chislehurst, Bromley, Greenwich and surrounding locations. Local property types vary, so extension work needs to be planned around the house itself. A semi-detached home in Bexleyheath may suit a rear kitchen extension, while a family property near Dartford may need a double-storey addition to create better space upstairs and downstairs.
The team can also discuss related improvements such as kitchen extensions, home refurbishments, structural alterations and layout changes where the extension forms part of a bigger upgrade. TRM Innovations Ltd specialises in extensions, refurbishments and kitchens, so the new space can be considered as a finished room rather than just a shell. Contact the team to arrange a visit and talk through what is possible for your property.
Free estimates
Realistic extension prices depend on the size, structure and finish
Single-storey and double-storey extension costs can vary because the work is affected by size, access, ground conditions, drainage, steelwork, roof design, insulation, windows, doors, electrics, plumbing and the level of finish. A compact rear extension for a larger kitchen will not be priced the same as a two-floor addition with bedrooms, bathroom work and major structural changes.
As a broad guide, many homeowners start by comparing extension costs per square metre, but a proper quotation needs to be based on the actual property. Design, planning, Building Regulations, professional drawings, materials, waste removal and internal finishing can all change the final figure. TRM Innovations Ltd provides free estimates so you can understand the likely cost, timescale and build approach before deciding how to move forward.
FAQs
Frequently Asked Questions
A single-storey extension adds space on one level, usually at the rear or side of the property. It is often used for kitchens, dining rooms, family spaces, utility rooms or home offices.
A double-storey extension adds space across two floors. This can create a larger kitchen or living area downstairs and an extra bedroom, bathroom or landing space upstairs.
Some single-storey extensions can be built under permitted development rights if they meet the required limits and conditions. This depends on the size, height, position, materials and property hiStorey.
Planning permission may still be needed for larger extensions, side extensions, properties in restricted areas or homes where permitted development rights have been removed.
A double-storey extension may need planning permission, especially if it affects neighbouring properties, sits close to boundaries, changes the roofline or alters the appearance of the home significantly.
Some two-storey rear extensions may fall within permitted development only if they meet strict rules. It is important to check this before making firm plans.
Most home extensions need Building Regulations approval. This is separate from planning permission and covers the technical standards of the build.
Building Regulations can apply to foundations, structure, insulation, drainage, ventilation, electrics, fire safety, windows, doors and overall construction quality.
The cost of a single-storey extension depends on size, design, access, materials and finish. A simple rear extension will usually cost less than a larger kitchen-diner with steelwork, glazing, plumbing, electrics and high-spec internal finishes.
TRM Innovations Ltd can visit the property and provide a realistic quotation based on the actual work required.
Double-storey extension costs vary depending on the size, structure, roof design, staircase or landing changes, bathroom work, bedroom layout and internal finishing.
Although a double-storey extension costs more overall than a single-storey extension, it can sometimes provide better value per square metre because the same foundations and roof area support more usable space.
A double-storey extension can be better value when the home needs extra space upstairs and downstairs. It may provide more room from the same footprint, which can make better use of the build area.
However, it is not always suitable. Planning restrictions, budget, roof design, neighbours, privacy and the existing layout all need to be considered.
A single-storey extension can take several weeks to several months depending on the size, groundworks, structure, roofing, windows, services and finishes.
Delays can happen because of weather, materials, inspections, design changes or unexpected issues with the existing property.
A double-storey extension usually takes longer than a single-storey extension because there is more structural work, more internal finishing and more coordination across both floors.
The exact timescale depends on the design, planning position, access, materials, roof work, bathroom or bedroom changes and the level of finish required.
Many homeowners can stay in their home during extension work, but it depends on the scale of the project and which areas are affected.
If the work involves the kitchen, bathroom, heating, electrics or major openings into the existing house, disruption will need to be planned carefully.
Yes. Kitchen extensions are a common reason for adding a single-storey extension. They can create more cooking space, dining space, storage and better access to the garden.
TRM Innovations Ltd specialises in extensions, refurbishments and kitchens, so the layout and finished room can be planned together.
Yes. A double-storey extension is often used to create an extra bedroom, larger bathroom, en-suite or improved upstairs layout.
The design needs to consider drainage, pipe runs, ventilation, floor levels, roof structure and how the new rooms connect to the existing landing.
In many cases, an extension can be designed to match the existing property using suitable brickwork, roof tiles, windows, doors, guttering and finishes.
Some homeowners prefer a modern contrast instead. TRM Innovations Ltd can discuss which approach is more suitable for your property and budget.
A rear extension is built onto the back of a property. It is commonly used to create a larger kitchen, dining area, family room or open-plan living space.
Rear extensions can be single-storey or double-storey, depending on the property, planning position and the amount of space needed.
A side extension uses space to the side of a property. It can be useful for semi-detached homes, detached homes or properties with unused side access.
Side extensions need careful planning because boundaries, drainage, access, roof design and neighbouring properties can affect what is possible.
A well-built extension can add value when it improves the layout, increases usable space and suits the property. Larger kitchens, extra bedrooms and better living areas are often attractive to buyers.
The value gained depends on the area, property type, build quality, design and how much the project costs compared with local house prices.
Most extensions benefit from proper drawings, especially where planning permission, Building Regulations approval or structural calculations are needed.
Drawings help clarify the design, dimensions, materials, layout and construction details before work starts.
Ask what is included in the quote, whether similar projects have been completed before, how long the work may take and what could affect the final cost.
It is also sensible to ask about insurance, Building Regulations, planning, waste removal, access, payment stages and how changes are handled during the project.
Yes. TRM Innovations Ltd is based in Bexleyheath and covers Dartford along with surrounding areas across Bexley, South East London and nearby Kent.
This includes Welling, Sidcup, Bexley, Blackfen, Erith, Crayford, Abbey Wood, Eltham, Chislehurst, Bromley and Greenwich where suitable.
TRM Innovations Ltd has been running since 2014 and specialises in extensions, refurbishments and kitchens. This makes the company well suited to homeowners who want the structure, layout and finished living space considered properly.
The team offers local building knowledge, practical advice and free estimates across Bexleyheath, Dartford and surrounding areas.