Trimble Architects

RIBA Architectural Services

Phone Number: 020 8538 9303

Mobile Number: 07785711635

Are you looking for a loft conversions architect in London? Our Twickenham based RIBA chartered architect offers a complete service for planning and converting your loft space. Contact us to discuss loft conversion architect services for Hounslow, Twickenham, Richmond, Kingston Upon Thames, Teddington and South London.

Loft Conversion Architecture, Design & Planning Specialists

Look no further than Trimble Architects if you're seeking a reputable and qualified London architect to design and plan your next loft conversion project.

Our architects and project managers have significant experience assisting London homeowners in making the most of their existing attic space and increasing its value.

Whatever your needs are, we will develop a gorgeous design that will boost the value of your home while also significantly expanding your living space.

Bespoke Loft Conversions in Architect London

Our loft conversion team throughout London provides high-quality bespoke loft conversions throughout London and the home counties.  

We have completed a number of bespoke loft conversions in architect London that are completely suited to the client's unique needs and tastes. A basic flat roof dormer is the most common style of loft conversion.  

This is a structural addition that extends vertically from the original roof's slope, forming a box shape. This loft addition requires no major adjustments and allows for the installation of standard windows. A flat roof loft conversion can add a lot of space for people who don't have the biggest of houses.

Types of Lofts

We provide a variety of loft conversion types such as a dormer, mansard, hip to gable, L-shaped, and Velux loft conversions.  

Our construction crew will remodel your home, providing you with extra living space and improving the value of your property.  

We want to make the loft conversion process as simple as possible for you from start to end, keeping you informed and involved at all times. Architectural drawings and structural calculations are followed by a preliminary survey and design in our procedure.

After that, the designs will be utilised to create a quote. When you accept our quotation, our architects will apply for planning approval, start construction, and then finish your new loft conversion.  

Our staff is always available to go through any area of the project in further depth. A loft conversion is an excellent option to expand your living space, whether your family is growing, you're renting out a room, or you simply want a new study or office.  

This is a less expensive alternative to moving, and it will increase the value of your property if you decide to sell it later. Regardless of the scope of the project, we will design a loft that represents your style and meets the needs of your lifestyle.

Dormer Loft Conversions

One of the most cost-effective ways to increase your living space without sacrificing yard space is to convert your loft.

When there isn't enough space in the yard and the only option is to rise higher, dormer loft conversions are particularly prevalent in urban areas in the United Kingdom. In recent years, improving your home rather than relocating has become increasingly trendy.

Among the most common types of loft conversions in the UK are dormer loft conversions, which are roof extensions that add height and square footage to a home.

Dormers are usually installed on semi-detached or terraced houses - dormers are roof extensions that extend vertically to add floor space. Dormer lofts are box-shaped structures with 90-degree floor walls and a pitched roof.

In contrast to a Velux loft conversion, a dormer conversion necessitates structural changes to your roof. Since work is done from scaffolding outside your home, this form of loft conversion causes the least amount of interruption. 

There are several different varieties of dormer loft conversions, and which one is ideal for your house will be determined by the type of property (terraced, detached, or semi-detached) as well as the present roof size and form.

Mansard Loft Conversions 

Mansard loft conversions, as opposed to dormer loft conversions, involve more substantial changes to the building. The roof has two slopes: the upper slope is approximately level, while the lower slope is nearly vertical at 72°. 

Mansard loft conversions are often constructed by elevating the gable or party wall on both sides of the home. This will produce a profile for your mansard, allowing you to build a timber frame.

Francois Mansard, a famous French architect who created residences in the 17th century, discovered the Mansard loft conversion. Mansard built residences with lofty, expanded roof surfaces.

Our team understands that Mansard loft conversions are more challenging than other types of loft conversions. It does, however, provide a significant amount of living space to residences. The additional area normally extends over the place of the roof with this form of loft conversion.

With a mansard loft conversion, you'll have enough room to add a bathroom, bedroom, entertainment area, or home office. This will significantly raise the value of your home.

This type of loft conversion works well in terraced, detached, and semi-detached houses.

Modern construction methods have made adding an extra level to a home with a mansard loft conversion, named after the renowned 17th-century architect François Mansart, more popular than ever.

This type of property improvement adds space to the roof of the house, but it is time-consuming. The conversions are typically large enough to permit numerous room additions, depending on the design.

It can, for example, house two more bedrooms and a bathroom.

The finishing may be done in a variety of ways to reflect the design of the property. Since most mansard conversions include structural changes to the roof's design, they need planning permission.

Mansard loft conversions are offered in several styles, including an L-shaped conversion - this type of conversion can create more space and have a greater impact on your property's value; this is the best conversion to create an open-plan bedroom with an ensuite bathroom. Two-tiered mansard roof - a double mansard loft conversion is offered in addition to the standard mansard conversion.

The home is distinct in that it has a Mansard attached to the front. This type of loft conversion is prohibited in some areas.

Mansard conversions are prevalent in densely populated areas when side and back yard space is restricted, or where homeowners want to save garden space by not constructing a ground-floor expansion. They are appropriate for a Victorian townhouse as well as a modern semi.

Hip To Gable Loft Conversions

A hip to gable conversion is suitable for homes with hipped roofs, which are inclined on one side of the house.

This kind of roof is commonly found on semi-detached and end-of-terraced properties in London and the home counties.

A hip to gable loft conversion will raise your head height to meet building requirements, allowing you to make greater use of your loft's interior floor space.

Hip to gable loft conversion is an excellent solution to solve storage and space problems without the inconvenience and expense of moving. Hip to gable loft conversions maximise floor area and height, and they can contribute significantly to the value of your home.

This is one of the most popular types of loft conversions, as it maximizes floor area and head height.

Check with your local estate agent to see how much a loft conversion will increase the value of your property, regardless of where you live.

The biggest advantage of a hip to gable loft conversion is the added space. Straightening up the sloped ceiling provides additional headroom, allowing for larger bedrooms and baths within your floor design. In general, the choices for converting a bungalow's loft are the same as those for a two-story home: adding a loft room, a dormer loft conversion, a hip to gable loft conversion, or a mansard roof conversion.

L-shaped Loft Conversions

One of the greatest loft conversion alternatives for increasing interior space and boosting headroom is an L-shaped loft conversion.

This type of loft conversion provides a number of layout options, including more than one room. An L-shaped dormer window is used in the L-shaped loft conversion. The two dormers in the L-shaped loft conversions intertwine into a corner.

The bigger end of the dormer is usually attached to the roof, while the smaller end is placed into the roof of an existing back expansion. The L-shaped loft conversion can give a headspace similar to the first-floor design.

An L-shaped loft conversion on a Victorian or Edwardian terraced property can result in a second room. Since this form of loft conversion requires a back addition, L-shaped conversions are only suitable for specific types of London houses.

Victorian and Edwardian terraces and end-of-terrace residences are a wonderful alternative for such a loft conversion, as most of these houses include a rear extension that forms the desired L-shaped roof.

Velux Loft Conversions

We provide Velux loft conversions, which are among the most popular and straightforward of all loft conversions. It is the cheapest way to enhance interior home space in the loft, and it does not even require planning approval.

In comparison to other loft conversion styles such as a dormer, mansard, and hip to gable, the Velux loft conversion takes very little construction and also causes a very little interruption.

Roof light loft conversion or skylight are other names for a Velux loft conversion. Velux loft conversions are without a doubt one of the most simple and cost-effective ways to increase headroom and maximise available space.

It also aids in gaining more natural light with good ventilation. In comparison to other types of loft conversions, such as hip to gable, mansard, and dormer, Velux loft conversions are less disruptive and need substantially less building work.

Our skilled loft conversion London staff guarantees that no harm is done, with maximum outcomes and no fuss by following all necessary procedures. Velux windows on the roof are required for that fantastic livable area.

We install this type of window as a loft conversion firm because it does not pitch out from the roof as dormers do, but instead stays in line with the current angle of the roof to enable natural light to stream in without affecting the roof structure.

Loft Conversion Architects Near Me

If you are looking for a London loft conversion architect get in touch today. Call 020 8538 9303 to discuss your requirements. Trimble Architects works with clients throughout London and the surrounding areas including:


Loft conversions are frequently possible without the need for complete planning authorization. You could just require a Certificate of Lawfulness from the council.

If you wish to carry out your loft conversion under allowed development, consider the following rules. Please keep in mind that if you reside in a conservation area, a block of flats, or on designated land, you may need full planning permission notwithstanding the preceding advice.

In order to be considered approved development, your loft conversion must meet the following conditions, according to the Planning Portals Guide to Authorized Development: Any additional roof space shall be no more than 40 cubic metres for terraced buildings and 50 cubic metres for detached and semi-detached residences.

If your house confronts a highway, your loft expansion cannot extend beyond the plane of the present roof slope. You must employ materials that are the same as those used in your current home.

The extension cannot be taller than the current roof's highest point. Under permitted construction, a balcony cannot be installed. To safeguard your neighbours' privacy, any side-facing windows must be made of opaque glass. 

They cannot be opened until they are higher above the level of the eye (specifically 1.7m above the floor height). 

Roof expansions are not permitted to overhang the existing roof. They must be placed back from the original eaves by at least 20cm. (Unless it's a hip to gable extension.)

Suppose you are investing in a loft conversion to make it a playroom, upon completion. In that case, there are a range of regulations to follow - but aside from that, it is safe and approved, so you don't need to worry about your child falling through the roof or injuring themselves.

The most common application for a loft conversion is a bedroom with an ensuite, which is a terrific way to increase space within your home while also increasing the value of your property by adding another bedroom. Although designs and styles are frequently the first thought for homeowners, other aspects of a loft conversion, such as bathroom plumbing, may go neglected.

If you're planning a loft conversion with an ensuite, this best chance of increasing the value of your property or a new home.

Alternatively, a legal loft conversion is doubtful if your roof is lower than 2.2m since the completed height within the loft would be less than 2m. To get the necessary height for a liveable loft space, the existing ceilings in your upper rooms can be removed and the new structural floor erected at a lower level than the original ceiling. While this lowers the original height of your upper rooms, it provides the necessary height for your new loft conversion.

If you're not sure whether or not this applies to you, feel free to connect and discuss it with us and we can advise you.

A permanent stairway to your new loft conversion is required regardless of how much space you have available - little or huge.

Numerous variables will be reviewed, as with prior suitability studies, to ensure the staircase is safe and appropriate for the purpose. 

A permanent staircase to a loft conversion is necessary by current rules for the formation of a liveable area, thus it is an important part of the build regardless of the available space – whether tight or with plenty of room to spare. There will be various considerations, as with the other suitability assessments, to ensure the staircase is safe and appropriate for the purpose. 

Consider where your stairs will begin on the floor below, as well as the space you will lose to accommodate it, as well as the headroom required in the loft where the opening will be formed. Similarly, the limited space will affect how steep and narrow the steps may be. 

A team of builders and building codes regulate the crucial proportions of the new staircase, including the proper pitch, to avoid trip and fall dangers. Your new staircase must begin someplace that does not interfere with the current arrangement of the home, and it must have a minimum height of 2m headroom at all times until it finishes in the loft.

In some circumstances, the new staircase can mirror the previous stairs and continue upwards without requiring extensive remodelling of the level it begins on, but in other cases, this will place it in the eaves of the roof, requiring a dormer to generate the necessary headroom.

A continuous layer of insulation installed over the rafters will eliminate cold bridging. This loft insulation approach also eliminates cold bridging, although it may limit headroom.

This issue is normally avoidable in new construction, but it might be problematic when converting an old roof. The most practical approach for insulating a loft is to install the majority of the insulation between the rafters, with a little supplementary layer connected to the bottom of the rafters. This is when insulated plasterboard comes in handy.

Good architects and builders incorporate this necessity throughout each project, and if the submitted information doesn't fit the standards for any reason, the home extension cannot proceed.

Our builders always utilise the latest technologies when providing additional room to your home and increasing your home value. For more detail, get in contact with us.

Most loft conversions are constructed to provide extra space. However, the loft extension can't exceed the existing roof slope. loft conversion requirements and building regulations require the structural strength of the additional floor to be sufficient, that there must be a secure fire exit, safely engineered stairs to the new level, and acceptable sound insulation between the conversion and the rooms below.

What's the Cost of Loft Conversion?

A loft conversion typically costs between £20,000 and £60,000. Each loft conversion is unique, and the cost will be decided by a variety of criteria, including the design of your home, its location if you require full planning approval, and, of course, your budget. 

These factors will determine the sort of loft conversion you choose in order to maximise space and usefulness for your home. 

You will normally have to pay an application fee if you need to apply for planning permission for your loft conversion. The price of planning applications varies substantially. 

Renovations and additions to a single dwelling house in England, Scotland, and Northern Ireland normally start at £202 to £206 and escalate from there. In Wales, a loft expansion planning application can cost about £230. 

Certain applications, such as those for listed structures or those to be destroyed in a conservation area, have no application fee.

Do I need Planning Permission for Loft Conversion?

Under Permitted Development, homeowners can usually extend their loft without filing a planning application.  

Our team of experts can guide you through the process and ensure that your loft conversion complies with Permitted Development standards.  

If certain restrictions and requirements are fulfilled, a loft conversion for your home is deemed authorised for development and does not require permitted development rights.  

A party wall agreement is a legal agreement provided by any neighbours who may be impacted by your loft agreement or other improvements. The Party Wall Act of 1996 governs this and gives building owners rights that go beyond common law.

Will a Loft Conversion Add Property Value?

Converting your loft is frequently the most cost-effective option to increase the value of your home.  

According to recent research by Nationwide Building Society, a loft conversion in the UK may add up to 20% to the value of your house, and if you want to convert your loft in London, your property worth can increase by 25%.  

Of course, many of the advantages of a loft conversion will be realised only if the construction project itself is successful. Certain frequent mistakes can occur throughout the design and planning phases of a loft conversion, and the majority of them can be avoided. 

If you properly plan your loft conversion, you will not only receive wonderful results, but the process will be a lot less stressful for everyone involved.

Adding a Loft conversion to your property

If you want to correctly convert your property, you will require an architectural design, which may sound fancy but is the most important for creating your ideal home.  

Loft conversions, in particular, are in high demand; they may be turned into a living room, storage, or whatever you choose, therefore, architectural designs are needed in order to map out your space. 

Loft conversion drawings are necessary since they reflect the intended design and build of the loft conversion. This will provide you with an idea of how your loft could develop in the future.  

Architectural design and build plans are often necessary when dealing with loft conversions.  

It's in people's rights to have more space when they need it; there is a wide range of loft conversions to choose from depending on the type of house and roof you own.  

Feel free to read through our trusted site and find what you need; for any reason you aren't finding what you need to know, don't hesitate to email us your questions and we'll provide the results you're looking for. We're always happy to share our expertise. Please browse our terms and conditions to locate the information you want.

Our loft conversion architects

Our loft conversion experience and advice assist many places that are unable to obtain reliable architects for various reasons.  

Our expertise and experience in this sector assist customers in getting what they want in a loft conversion - simply leave it to us and we'll make sure that your every request is included in our plans.   

We're always willing to provide a helping hand, which means we'll work even harder to get you the space you need on time and within budget.  

In any case, we keep in mind how valuable your time and patience are. From the beginning to the end, we prioritise efficiency to ensure that your loft conversion looks and feels wonderful.  

We love making homes look and feel efficient by adding space to their lofts. Lending a hand in making your loft great is what we're all about; providing the right conversion and changing your loft into a hospitable space on time is what we're great at. 

In any case, we love providing homes with quotes so they can have the opportunity to think their conversion through at a time that suits them. 

We always bring our high levels of experience to every single home, making sure not to make the process difficult at all - we enjoy leaving homes with a touch of architectural magic. 

We don't take chances or make the building process difficult, so when you're ready, we're happy to give both our experience and a quote to you.

Improving your living space 

Having a comfortable living space is what makes the world go round, therefore, we love providing this chance to homes. Working through every single detail is important to us, as we like to eliminate any possible issue; with us, your lofts will be designed and converted to perfection - both inside and out. Our experience never ceases to fail us.  

Our experience ensures that the right loft amendments are made for you to live comfortably.  

Simply look through our guide and choose the conversion best suited for you. We are always open to preferences and compromises when it comes to you finding the best way to enhance space in your home.  

Any important detail depends on you, and with our transparent reputation, we can make sure that no issues are left to fester. Giving homes more space to live is what we strive towards every single time. 

Our guide and articles can surprisingly provide and confirm any answers you need as well as provide a step-by-step guide on how to go about your loft conversion.  

Our experience and guide can help ensure that your conversion goes as smoothly as possible; any promises will be diligently fulfilled. Summer months, such as March, are ideal for loft conversions due to longer days and higher temperatures across the region.  

Since there is less risk of adverse weather and less rainfall, this time of year may be simpler for your project.

On any occasion, we always work alongside our clients so that any risk or miscommunication can be minimised through a simple enquiry. Utilising the architectural design plans that have been submitted is essential to any subject of loft-work. Therefore, we make sure to respond to any questions.

Planning your loft conversion

When we visit your address, we make sure to cover the basics of the complexity and regulations of our plans.  

When uploading and submitting these design plans, we always make sure to follow expectations and guidelines, as well as address any possible issues that could arise when the construction process goes ahead.  

Our team will always find ways to complete your loft conversion seamlessly with the best experience and techniques to date. With us, your expectations will be exceeded.  

When designing plans, we make sure that everything is addressed and explained to you beforehand so that you don't lose out during the construction process begins. Abiding by terms and regulations is our priority when visiting your home.  

It can be daunting when deciding what type of conversion you're looking for; therefore, our website is crucial to helping you deliver the right loft conversion for your home.  

Any issues can be addressed and prepared for - with our plans; there's nothing to be concerned about. We combat any tough circumstances with optional creativity to deliver the best architectural service for you. 

Our professionals always value your consent to any optional plans.  

Our services consist of permitted contractors and competitively priced fees that can lead to you having a perfect loft conversion.  

Most importantly, with these services, you are guaranteed to have saved money by the end of each year. Our professional engineers can achieve the best conversions without them becoming costly. Each job is managed with efficiency and features valuable meetings and support at each stage. Each of our professionals engages with loft conversions in the best ways possible.  

If you're wondering or interested, our professionals are great at transforming your space without the usual hassle - we keep all details secure and under control, so you can feel safe having your loft transformed into a luxury space.

Trimble Architects

Based in Twickenham

South West London

Call 020 8538 9303 to discuss your requirements.

RIBA LOCAL ARCHITECT SERVICES Hounslow, Twickenham, Richmond, Kingston Upon Thames, Teddington
 ARCHITECT  Hounslow, Twickenham, Richmond, Kingston Upon Thames, Teddington

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If you require a New Build House get it touch today. We offer RIBA chartered architectural services throughout Hounslow, Twickenham, Richmond, Kingston Upon Thames, Teddington and South London. We look forward to hearing from you!

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