Semi detached loft conversions - costs and FAQs

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Semi detached loft conversions costs and FAQs

 Loft space is already there and redundant, simple loft conversions may not even require planning permission and, the cost of a loft conversion for a semi-detached house compares favourably with the financial outlay of an equivalent extension. Depending on the style and type of loft conversion you choose plus the ultimate finished accommodation, the cost of a semi-detached loft conversion will range anywhere from £20,000 through to £65,000.

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A semi-detached property will always have the option of a side extension on the non-attached side of the property or even a rear extension but extensions are not always desirable for a number of reasons:-

  • There could be a much-needed garage on the free side of the house
  • A rear extension will encroach into outdoor areas and garden space
  • Rear extensions are an expensive way to create ground floor accommodation; a full-height extension can often represent better value for money but is not always either possible due to the style of the house or permitted by the local planning authority
  • An extension may disrupt the external appearance and symmetry of the house
  • The property may already have been extended and these options exhausted

What are the advantages of a loft conversion on a semi-detached property?

There are numerous advantages of creating a loft conversion and these include:-

  • It increases accommodation whilst avoiding the hassle and expense of moving from a house you love and have invested in and which may be perfect in every other way
  • It saves poaching precious outdoor space from the garden or rear parking which is always the trade-off with an extension
  • You may not have the option to extend on the free side of the house if you use that area for parking or have a garage which is essential to your lifestyle
  • The loft space is already there and redundant
  • Simple loft conversions are very affordable and apart from the addition of skylights or Velux windows, are completely unobtrusive when it comes to the external appearance of the property
  • If you have a traditional or character home, then a loft conversion offers you the opportunity to create something super contemporary and open plan without compromising on the current interior styling of your home
  • A loft conversion can offer more accommodation options to a house that is already at full capacity and where there is no further possibility to extend to the rear or the side
  • A stylish loft conversion will uplift the value of your home by between 20% and 25%

What can a loft conversion offer to a semi detached home?

There are so many possibilities for this new space, here are just a few ideas:-

  • The Coronavirus will change working habits possibly permanently. Working from home has loads of advantages but one of the challenges has to be finding a dedicated and quiet space particularly if you have young children. A loft conversion can provide the perfect location for a home office and can also double up as a study area for children and teenagers
  • Install a space to work out or a home gym
  • Take your home business from the kitchen table to a bright, bespoke rooftop space fitted out to exactly suit your requirements without any intrusion into family life
  • Create a stunning master bedroom with en-suite for guests, a lodger or even bag it for yourself
  • Fit out a kitchen and open plan living area and link it via the staircase to a bedroom with en-suite on the floor below and hey presto, you have created two-storey self-contained accommodation for an elderly relative or grown-up child yet to fly the nest
  • Create a home cinema or media room freeing up the main living room downstairs for another function – perhaps a playroom, home office or study
  • Design a playroom or dedicated play space for little people which can grow and change as they do

What factors will affect semi-detached loft conversion costs?

  • Think about which type of loft conversion will best suit the style of your property – it’s not just about the internal accommodation you can achieve. Some homeowners use a loft conversion to radically re-style the external appearance of their home whilst others deliberately choose something much more de minimus and subtle which does not alter or detract from the aesthetics of their home
  • Planning regulations may restrict your choice of loft conversion particularly if you have a listed property or your home is sited within a conservation area
  • Determine your budget. Simple roofline conversions can cost as little as £20,000 but a dormer conversion or a mansard could come in at anywhere between £40,000 and £50,000
  • Think carefully about your choice of interior accommodation – kitchens and bathrooms hugely increase the cost whereas studio space or additional bedrooms will lower the final bill quite dramatically
  • What are you trying to achieve with the extra space? Does it enhance and complement the rest of the property or are you just needlessly doubling up?
  • Properties with water tanks in the loft will need to be re-routed and a header tank system replaced with an alternative
  • Additional accommodation will require heat and light and possibly also plumbing if you add an extra bathroom or kitchen, can your current heating and hot water system cope with the additional burden or do you need an upgrade to a new boiler?

A good roofing contractor can discuss the pros and cons of the different type of loft conversions with you to help you make an informed choice. They can also prepare estimates so you can see how the different costs pan out before making your final decision.

What is the timeline for a loft conversion on a semi-detached house?

The early process of sourcing an architect and a builder, preparing the drawings and achieving planning permission can take on average about two to three months without any unscheduled hold-ups. The architect’s job is to breathe life into your vision whilst the builder has to ensure that it is workable and within your budget. Once the builder has the drawings, he can prepare a detailed schedule of works and cost the project accurately. Expect all this to take about twelve weeks and this is without any unforeseen delays.

You will require planning permission unless your loft conversion is very simple and you will also need to obtain the agreement of your neighbour on the attached side of the property under the rules laid down in the Party Wall Act 1996. This statute is there to protect your neighbour from the disruption caused by your building project and any ensuing damage. Normally, your architect or surveyor will negotiate the Party Wall agreement or Award and this has to be in place before the works commence.

A simple roofline conversion will take between two and four weeks from the start of building, anything more complicated, around two to three months.

Which loft conversion type will give you the most space?

The dormer is the most common type of loft conversion. A dormer loft conversion creates an extension to the existing roof that projects vertically from the slope adding both extra floor space and valuable headroom. A dormer has a horizontal ceiling and vertical walls and this style is the most popular because it creates the most usable accommodation.

A flat roof dormer will offer you the most amount of additional space and if you don’t like the appearance of these aesthetically, then you can add a gable front and a hipped roof dormer to make it look more pleasing although you will cut down on the space available inside. This also costs more to build as it is more complicated. L-shaped dormers are also very popular and work really well for mid-terraced properties which can be quite hard to convert for maximum benefit. Some styles of dormer loft conversions don’t even need planning permission but don’t make that assumption across the board as it depends wholly on the exact specifications of each individual conversion. Do you own a bungalow? Click here to see the cost of a bungalow loft conversion.

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Frequently Asked Questions

What kind of objections could be raised to prevent planning permission for the loft conversion of my choice?

The main things which can stop a planning application in its tracks are valid objections from the attached neighbour and some contravention of existing planning legislation in terms of the design. A good architect will not aim to draw plans that are going to fail at the planning stage but it is really important to listen to his advice and that of your builder if there are aspects of your design which they think won’t pass. Always do your preparation very thoroughly to maximise the chances of the application going through the first time.

What other restrictions can there be on the choice of loft conversion type?

If your property is listed and/or in a conservation area then you may be limited on the type of loft conversion you can have also the choice of materials which you are able to use.  You won’t be able to do anything to the house which substantially and constructively alters its appearances so it no longer appears as a house dating from a particular period and in a particular style.  Planning officials will also always look at the impact of your conversion on surrounding properties – this is an important consideration whether the property is listed or not.

How can reduce my semi detached loft conversion costs?

Always seek at least three quotes – you will be surprised at the variation in price there can be for supposedly the same job. If you find a builder you really like then be candid about your budget and ask him whether there are things you can do to lower the cost. Altering the style and some of the materials can bring down the final bill but if you deviate from the original drawings then you will have to go back to the architect for new plans which may have to be submitted again as a fresh planning application if they differ radically from the original ones.

How can I fund a loft conversion?

Some homeowners approach their lender if they have sufficient equity in their property to support extra borrowing. This is usually done by way of a Home Improvement Loan or Further Advance and is secured on the property usually alongside the existing mortgage and for the remaining term; this can make the monthly payments attractively low compared to other forms of funding.

Some of the larger roofing companies offer finance packages by way of a third-party financial institution, a bit like the type of finance arrangements you see when you are buying a new car.

Which type of loft conversion will add the most value to my home?

The answer to this will depend on your property and how it is currently configured. The most valuable type of loft conversion is the one that best suits the style of your house and offers the maximum floor area without compromising this principle. Another factor to consider is what you do with the extra space. A master bedroom with en-suite may be lovely but if the house already has a master and en-suite or two bathrooms then the loft space is probably not being put to its best use. If you are not fitting a kitchen or bathroom then try and keep the area open plan; not only does this look quite spectacular when decorated and furnished but it will allow prospective buyers the flexibility to think about what they might do with the space, not quite so easy to do if it is already furnished as a kitchen or bathroom.

Will I receive any warranties or guarantees after the loft conversion is finished?

Your roofing contractor should give you a guarantee for the works as a whole, usually of a minimum period of ten years. There will also be specific manufacturer-based warranties relating to certain parts of the installation and some materials. Keep them all together safely in case you need to rely on them. They should also form part of your seller’s pack if you put the house on the market. 

We hope that this article has given you some insight into semi detached loft conversion costs!