Building House Extensions
Planning House Extensions
Whether you are building a new home or planning house extensions to an existing home, you are going to need building approval from your local authority. Even if you are simply opening up a wall or partitioning a room by erecting a new internal wall, most councils will insist on working drawings.
They won’t worry about issues like matching materials or style, but they will consider all the elements that relate to building codes and building standards.
House Extensions Options
There are various ways that you can extend an existing house. For instance you can go up and create a second storey or opt for a more straightforward lateral extension. If the pitch of your roof is sufficient, you might be able to convert this into an attic room. Alternatively you could add a separate freestanding structure with a link to your existing house.
Having said that your local authority isn’t going to be bothered with style, this is an element that is essential if the house extensions is going to look good. Materials should also match or look as though they have been chosen carefully. This means that if yours is a facebrick dwelling, the extension should be built using the same finish facebrick. If it is plastered and painted, it is best to match the paint colour. This isn’t always as easy as it might seem, since paint colors fade and from time to time manufacturers change their specifications.
Planning for a Building Extension
Sometimes, but not always, people do plan for future house extensions. This makes it a lot easier when it comes to adding on a room or converting space. As an example, where a future door is planned, building in a lintel at this point, and enclosing the door area with straight joints will make it easier to knock out the brickwork at a later stage. The fact that the bricks aren’t bonded beneath the lintel won’t be an issue, because the lintel will support those above.
Even so, you will need to be sure that the house extensions are correctly executed, with the correct foundations (unless of course you are going up, in which case you will need to have existing foundations that can take the weight of the new building extension), and where brick or block walls meet, these will need to be bonded, or joined in such a way that cracking will not affect the structure.
Types of House Extensions
These include:
- building a core house and then adding to it later according to existing plans
- converting a garage into extra living space
- converting an attic into habitable space
- constructing rooms in a roof where there is no existing attic
- adding or converting a cellar
- adding a conservatory, sunroom or pool room, usually with glass
Develop a Core House
If you are building and you don’t have the means to build the size house you believe you need, an excellent solution is to build house extensions over a period of time. Thoughtfully designed, it will never look incomplete.
Below are three drawings that show how a core house (coloured yellow) may be added to over time.
In the first drawing, you can see that it is a simple, compact two-bedroomed home. Both bedrooms share a bathroom and they are both the same size. Each room has built-in cupboards and there is a laundry cupboard in the passage outside the bathroom. The living area is open plan, with a bar counter “dividing” the living space.
In the second drawing, the kitchen has been extended, in such a way that existing plumbing is used, even though the sink changes position. An exterior door is added, linking to a courtyard with a washing line, and to a double garage. One section of the garage incorporates a storeroom, adjacent to a loo with a basin, accessible from the courtyard. The main bedroom is also included in this phase, although it could, of course, be built on later, since it is at the opposite side of the house. An en suite bathroom and more substantial cupboards are also included in the new plan.
In the third drawing, an open-plan lounge-dining room has been added (blue), along with a new entrance way and a guest loo. A swimming pool has also been included on the plan, though this could also be a separate phase.
Convert a Garage
This can be a very convenient and reasonably easy way to add house extensions to a house, although local authorities are usually strict in terms of upgrading the existing finishes. For instance you may need to have a ceiling installed, and lighting and ventilation might need to be upgraded.
Add a Sunroom, Pool Room or Conservatory
There are companies that specialize in glazed structure (or one where a polycarbonate material is used) that fit this category, though you can also have something designed and custom built.
Go into the Roof
Many older homes were built with attics that were intended to be used for storage. You might need to add windows and insulate the walls and ceilings to make the space habitable.
If there isn’t an existing attic, and the roof is high pitched enough, you might consider doing house extensions by building a room in the roof space. The basic concept is very similar to converting an attic, although structural alterations will be considerably more complex. If the pitch is not sufficient, you will have to extend the gable ends and increase the pitch of the roof.
In both instances you will probably have to add stairways that are easy to use.
In South Africa and other hot-climate countries, the roof space (and attic) in a house can become unbearably hot, so it is essential to pay attention to insulation.
Go Underground
Cellars are surprisingly uncommon in South Africa, but they are sometimes included in the design of a house, and these house extensions may be added at a later stage providing the foundation walls are high enough. Generally it is easier to add a cellar where the house has been constructed on a slope.
Just remember that for a cellar to be converted into a habitable space (even if only as a playroom), it must be totally dry (there must be a damp-proof membrane between the brickwork and the soil beneath ground level) and have sufficient light and ventilation. Usually this will entail installing artificial ventilation and electric lighting.
Apologies for taking so long getting back to you Gretchen – your query went to Comments and their was a gremlin in our system (we weren’t picking these up)! I have now added some information about arches that might be helpful to you and others who need this information. You will find it HERE.
I can’t imagine why it would have to go to the deeds office! Basically you probably need the approval of the BC and possibly plans approved by the local authority – but 25 sq m should fall under minor building works, in which case you would simply notify the local authority. I suppose there might be a clause the HOA has that requires extensions to be registered on the title deeds; I suggest you check this with them. In terms of any roof structure, you need to be guided by SANS 10400: Part L Roofs. There isn’t a Standard specifically for roof extensions. If you do need plans (and the planning department of your local authority will be able to advise) then you will need to enlist the services of a competent person. I have added links that should help you.
Hey Penny i am looking for regulations / standards referring to roof extensions onto existing buildings. I want to add a 25m squared Harvy tilled roof to my patio but its in a sectional title(BC and HOA approval) and the property manager seems to think the whole scheme needs to go to the deeds office to be re registered once iv done my alterations. Im hoping this is a addition that does not require approval
No Julian it is not acceptable.
Wayne, the first thing you need to do is get a professional to assess what can be done to sort out the damp problem. It may simply be due to a build up of water, but it may be necessary for you to take steps to get rid of the damp before you even consider further building. Water can cause a lot of damage and is often very difficult to pinpoint – because quite simply it flows everywhere.
But to answer your question, building walls and erecting a roof does not fall under minor building work and so you will need to have plans drawn up by a “competent person” and approved by your local authority.
Hi Penny,
Thank you for a most informative website! It has been very useful.
My wife and I bought a fixer upper home about four years ago and have been slowly bringing it back to life. We are struggling to solve a damp problem in the one room which has a patio built over it. The ballustrade is built up wall so there is no way for the rain water to run off and the builders never incorporated sufficient drainage, so when it rains the water seeps through into this room where the slab meets the walls. I use it for storage since it is not safe to occupy as result of the damp.
We have been considering enclosing the patio by building a roof and two walls, one on the western side and the other the eastern side, leaving the north facing side open with a steel ballustrade so we can still look out onto the garden. Essentially it would be a covered patio built of bricks and mortar. The cost effective route would be a steel structure to cover it, much the same as a carport.
With this in mind, would you advise that we still need to get plans drawn up and approved to start the process even though we want to raise a basic patio?
I look forward to hearing from you!
Regards,
Wayne
Brynn the City of Cape Town has new zoning regulations that came into effect in March 2013, that allow building on boundary lines, with certain restrictions. Generally this means that you no longer require neighbour’s consent. It is no longer relevant where your property is. Size of the plot is the issue. e.g. If your plot is between 350 and 650 sq m in size, then the street boundary building line is 3,5 m and common boundary building lines are 0,0 m for the first 12 m measured perpendicular from the street and 0,0 m for 60% of the total remaining linear distance along all common boundaries around the land unit, and 3 m for the rest (presuming your property is zoned single residential – “The single residential zones are designed to provide locations for predominantly single-family dwelling houses in low- to medium-density neighbourhoods, with a safe and pleasant living environment.”)
“Where a building is permitted in this zone within 3 m of a common boundary, the height will be limited to 4 m measured from base level to top of roof.”
“Notwithstanding the provisions in subsection (c)(ii) (which is what I have quoted above), within the first 12 m along a common boundary measured perpendicular from the street boundary line and where a building is not set back from such common boundary, the height is determined in accordance with the ‘Table of floor factor, floor space, height and building lines in Single Residential Zone 1’;”
There are additional requirements including:
“Window and door placement
Any portion of a building which contains an external window or door facing onto a common boundary shall:
(i) be set back a distance of at least 1,5 m away from such boundary; and
(ii) the portion of building to be set back from the boundary shall include the door or
window, together with such additional length of wall as is required to make up a total minimum length of 3 m.”
“Garages, carports and outbuildings
(i) A garage, carport and outbuildings are permitted within the common boundary building line provided that the garage and carport do not:
(aa) extend higher than 3,5 m from base level to top of roof;
(bb) contain more than a double garage façade; and
(cc) exceed a width of 6,5 m.
(ii) For land units of 650 m2 and less, a garage or carport is permitted up to 1,5 m from the street boundary provided the garage or carport:
(aa) is not higher than 3,5 m from base level to top of roof;
(bb) does not contain more than a double garage façade; and
(cc) does not exceed a width of 6,5 m.
In the table, maximum floor space = n/a and maximum height to wall plate = 8 m & to top of roof = 10 m.”
I hope that helps. If you comply with these, you shouldn’t have any problem getting your plans passed.
There shouldn’t be a problem building over the sewer. If the line does need to be moved you will need to get a registered plumber to do the work. But in any case, you will need approved plans to do the extension, and if the council needs the sewer to be moved, they will tell you.
Hi Kirsty,
The building regulations refer to the usage of any given space in a building not wether the structure has been altered or not. It seems as if the garage/storeroom/maids quarters/garden cottage/bathroom/kitchen has been considerably altered you should have got plans drawn and planning permission before starting to build. You should get a “competent person” to draw up some plans and submit them ASAP. If at any time in the future you would like to sell you will have a problem because what is being sold and the registered plans differ and you could be penalised and delay the sale.
Hi Ryan,
You can install a carport on a boundary wall if you have plans and you get them approved by council. You must also get permission from from the relevant neighbours and submit those with your plans as well. You can read more about boundaries here: Boundary Walls & Fences and here Boundary Lines and here Minor Building work. The regulations for windows is determined by what the rooms are used for, if any of them are for a toilet then it is not only light but also ventilation that is needed, you can read more here lighting-and-ventilation
Hi Ismail,
The building of the carport will fall under >>minor building work<< (Click the link to read more). But enclosing your pool sounds as though it is more than the minor building law allows so you may well need plans and approval from council. I suggest before you do anything contact your local building inspector and ask their advice.
Hi Mike,
Have a look at this page on “Minor Building Work” As you will see this should be considered minor building work and there are no plans needed for what you want to erect BUT you will need to notify the municipality in writing that you are putting a covering over your existing patio.
Zoning is a local authority issue. Contact your local authority and ask for advice.
Denton to add to my previous reply; I have discovered that some municipalities do have a restriction on how much land you can build on. But this may also relate to the zoning of the property. I have found a clause in the City of Cape Town’s by-laws that refers to coverage for buildings on a specific type of land unit that may not exceed 60%. So you will need to contact your local authority and check with them.
Hi there, I am planning to extend my home by about 60m2. The original plans indicate the sewer line from the kitchen and bathrooms is running past the side of the house where I am planning the extended portion, only to connect to the main line on the perimiter of the erf. My question: may I build on top of the sewer line or must the line be moved so that it is not under any structure?
I would have liked to see infos about staff quartes on the property or a definition of dwelling. I am about to buy a house in SR zoning as a Single Dwelling but see there is a staff quarter in in own building on the boundary wall with a very small room for a bed and a shower/toilet. I don’t know if I can renew/rebuild that at all.
No not specifically, but there are building lines that you have to accommodate. The article on this page of our sister site http://www.ownerbuilding.co.za will give you more information. If you want more detailed information I suggest that you contact your local authority.
Hi…I am looking into donig some extentions on my house. I have a small erf (+- 350m2). Is there a restriction on how much land I can build on?….ie only 50% of the land. Thanks for the help
Debby, From what you say you are wanting to take over the lease of a property from a business, (rather than “a lease of a business”) – that’s a bit confusing for starters. But let’s see if this helps you.
If the current lessees (tenants) have made illegal alterations to the buildings, the owner of the property needs to take some sort of action – not you.
It is possible to submit rider plans for work that has already been done (i.e. you don’t necessarily have to destroy the illegal sections of the structure and then start again). However, there may be hefty fines involved. In any case, the owner of the property is the only person who can appoint a competent person to draw up and submit plans. See this LINK for more on competent persons and the law.
The owner must either do this for his own account, or hold the current tenants liable for damages. There is no reason for you, as the new tenant, to be held liable.
If you go ahead and start further alterations, you will not only be liable for costs, but could eventually be held liable for the damages mentioned above. So sort out the problem first – not afterwards.
A last thought, usually the owner of a property would need to approve someone taking over a lease agreement. So be very careful.
Mornig
I would like to find out, we are wanting to take over a lease of a
business but it has been brought to our attention that they have made
alterations to one of the buildings withour having an approved plan,
how can we rectify this and what would be reqquired. We have been told
that we would have to restore its original shape, break everything
down and then apply get it approved and then rebuild. Please can you
assist us with this query
Hi Imran,
The specifications for loadbearing walls will depend on the weight that the wall will have to support. This needs to be calculated and designed by a structural engineer. Your best option is to contact one of the pre-stressed concrete manufacturers in Durban who have the engineers specifications for all their products on hand and will be able to help you. One word of caution, in terms of the new regulations plans have to be drawn up and submitted by a “competent person” please have a look at the link.
Hi Frik,
I have contacted Simon from Beautiful Structures in Johannesburg (011 795 1827) and he confirms that most bolt-on structures are considered “Minor building work” and do not usually need plans. Where the floor area is increased the concrete must be mixed to the specifications that suits the load that the floor must carry, see our “concrete mixes” page. If you are concerned that the load is such that reinforcing might be needed then you should contact a structural engineer for advice.
Hi Marion, That sounds very strange. Please ask him what law this is (and let me know) – because the building regulations (the law) changed in 2008, and the guidelines (SANS) were published progressively until last year. I am not aware of any new law! However, there might be a new by-law in your area. As you will see from this article on Boundary Walls and Fences (click the link), the local authorities have the power to make demands in terms of what they look like. There is an article about boundaries and boundary walls on our sister site HERE’S THE LINK.
My suggestion is a) find out which law this guy is referring to; and b) call you local planning office and ask them what the standard distances are in terms of boundaries and building lines.
Hi, i am currently busy doing extensions around my house, like building a garage. The guy who draw the plans told me that there’s a new law which came into effect from 1st of March 2013(is that true), and apparently your veranda in front of the house, must be 1.5 metres from the boundary wall, and the garage must not exceeds 6.5 metres in width,leaving now a 1.2 metres from my neighbours boundary wall and the garage wall(which is a waste to me), and the garage doors must be 2 metre from the boundary wall. Just need advice pls
You can get this from your local authority.