Home extensions: What should you consider?

By Isabelle Coetzee

While admiring your home on a sunny afternoon, you might think it’s time to tackle that home extension you’ve envisioned since the day you signed your lease.

This is an exciting thought, and you might find yourself sketching a rough draft on an exam pad or exchanging ideas with your family members.

But before this can go forward, you need to consider the regulations and costs of your home extension, as well as the impact it will have on your insurance premiums.

The most important building regulations

Renn Hartmann, owner and principal architect at VURV Architects, explains that the National Building Regulations (NBR) and Building Standards Act provides a set of standards and guidelines that govern building and construction work in South Africa.

“While most regulations are more technical in their nature, of considerable importance to the home owner when planning a home extension is the application of energy regulations,” he points out.

The NBR implemented a new regulation in 2011, called SANS 10400-XA Energy Usage in Buildings, which attempts to relieve pressure from the national electricity grid by reducing energy consumption in buildings, both private and commercial.

According to this regulation, “All new buildings must comply with the regulations, as must any additions and extensions to existing buildings.”

Hartmann believes this will have a negative impact on the cost of construction, but it will later save you money in terms of the operational cost of running your home.

“On average, South African homes are notoriously uncomfortable to live in, being cold in winter and hot in summer, and often relying on air-conditioning to regulate comfort in the home. When applied correctly, the energy regulations can completely mitigate the need for artificial heating and cooling in the home with cost savings as a result,” says Hartmann.

This regulation will only apply to the home extension and the surrounding areas that may be affected by the changes.

However, Hartmann warns that, “The comfort level in your home will be imbalanced if your extension addresses and complies with Energy Regulations (contains sufficient insulation, double-glazing, etc.) but the remainder of the existing house is left as is.”

“Although regulations don’t require the entire house to be altered to comply with energy regulations when planning an extension, I always suggest to our clients that we treat the extension and existing home as one entity in the application of Energy Regulations,” he adds.

The costs that can’t be avoided

Prior to construction, it’s important to consult professionals, such as an architect and a land surveyor, to ensure that your home extension is well-planned.

According to Hartmann, at the very least you should consult an architect and a structural engineer. This could cost you the following:

  • Architect: Fees typically range anywhere from 4%-12% of the construction cost (Their fee will be relative to the size of the company, expertise, qualifications and level of service they provide).
  • Structural Engineer: Guideline fee of R150/m2

“Even though their fees don’t correlate into a tangible part of your build, their services and expertise are invaluable. With the correct professional advice and guidance, building costs can certainly be reduced and unknowns relative to the alteration of your existing house can be minimised. A well designed and well-built home extension can incrementally add to the value of your property,” says Hartmann.

He cautions that building rates per square meter, which are often referred to when considering costs, are in fact inherently inaccurate.

“Dealing with alterations to the existing structure of your home is never straightforward. Although your architect should ascertain sufficient information from existing drawings of your home and from site inspections, there are inevitably unknowns that pop-up during construction,” says Hartmann.

“These unknowns very often lead to escalated building costs. Be prepared to deal with the uncertainty of altering the existing structure of your home to incorporate the extension,” he adds.

Hartmann offers the following advice on how to reduce costs:

  • Be upfront with your architect about your budget from the get-go – This will allow them to correctly design and specify your project and offer guidance as to what may or may not be achievable within your budget.
  • Be open to the creative use of space – Try not be too prescriptive about each space being dedicated to one function. For example, home extensions often result in intermediate transition space between the existing home and new extension. This space could be used as a small study or library space. If you’re open to giving different spaces a multitude of functions, you can reduce the floor area of your home extension and hence the overall cost thereof.
  • Keep it simple – An elaborate floor plan, intricate design details, and ornate finishes will eat away at your budget. Work with your architect to achieve a simple, functional, low-maintenance home extension. This works hand-in-hand with being creative in the use of space – the simpler the extension is, the more adaptable it will be to different functions.
  • Cheapest is inevitably not cheapest – Yes, materials and finishes for the construction of your home extension should keep in line with your budget. But simply selecting the cheapest of everything can land up costing you more down the road in maintenance or replacement costs. Place value on what you are paying for, and draw upon the expertise of your architect in selecting good quality products that are in-line with your budget.
  • Vet your potential building contractors – A personal recommendation from trusted family or friends is always beneficial in selecting a building contractor to undertake your build. I advise clients to obtain three to five quotes from different building contractors. These building contractors should ideally have past experience with home extensions of a similar scale and specification to yours. Have an introductory meeting with potential contractors and ask for contact details of past clients of theirs. If possible arrange a visit to a past built project to get an idea of the quality of their workmanship and a visit to a project under construction to get a feel for their site operations (a messy unorganised building site is often an indication of the care the building contractor will be applying to the build). All home building contractors in South Africa are also required by law to be registered with the National Home Builders Registration Council (NHBRC).

Should you tell your insurer?

With all the focus on creating something new, it’s easy to forget about your existing home insurance provider and whether you should keep them in the loop. But not doing so could be disastrous.

“During a renovation, unforeseen damage can occur to the homeowner’s possessions or the house itself,” says Lynda Brown, regional manager at MUA Insurance Acceptances.

“In the event that the policyholder does not disclose the alternation at commencement, they run the risk of having their claim for damages that occur during the renovation process be rejected,” says Brown.

She explains that when making changes to your home, you need to allow your insurance provider to re-assess the risk and apply revised terms to the insurance policy for the duration of the construction.

“Another concern for the homeowner when they do renovations, would involve their movable property within the home,” says Brown.

She adds, “The increase in risk is evident when numerous contractors are working within the home, and therefore it is not uncommon for insurers to restrict theft or attempted theft of movable items, where the policy will only pay out if forcible entry into or out of the premises is evident.”

In light of this, she advises homeowners to place their most valuable items, like jewellery and collectables, in a safe or bank vault during the construction of home extensions.

“Best practice prevails in these situations, and homeowners are advised to contact their broker or insurance provider prior to commencement of any alternations,” concludes Brown.

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