1st timers guide to cost efficient house design
So you are considering building your own dream home? The majority of people building their own homes are often caught off guard regarding budgeting of the project and this always results in a really unpleasant experience for the first time builder. Being conscious about budgeting can save you a lot of headache during the building process and might eliminate most of the nasty surprises. Following is a few pointers to keep in mind when designing and budgeting for your proposed home:
SIZE
The first thing to consider is to build a single storey or double storey home. Factors that will influence your decision might be amongst others: Stand size, soil conditions, views and of course cost. The cost of building a double storey is not necessarily a lot more expensive than a single storey as the cost of the 1st floor slab might cancel out a big percentage of the cost of the foundations and treating of the ground and ground floor slab especially if the ground conditions are of poor quality.
MASONRY
When 1st time builders are planning and designing their new home they often try to save on the masonry and frequently compromising on the comfort or aesthetics of the house. Typically the masonry work in a home building project only amounts to about 8-10% of the total project cost and therefore does not make sense to try and cut costs by cutting on the brickwork. One can of course argue that all these walls needs to be finished with plaster & paint or other finishes, but for the most part there does not really rest a cost saving in the brickwork. Remember, a great design can be created really inexpensively with only using brick features or niches in and outside the house.
MASONRY SHAPE
One thing one might want to consider is the shape of the floor plan. If you really need to save on the masonry, there can be a substantial saving in keeping away from long rectangular or complex shapes with a lot of direction changes. Where possible, try to keep the shapes as square as possible and eliminate unnecessary internal walls and direction changes in walls. As a guideline, consider the following: A 10x10m square shaped home amounts to 100sqm using 40m of wall. A 20x5m rectangular shaped home also amounts to 100sqm but the length of wall used to create the same area now being 50m.
ROOF MATERIAL
The different roof material considerations might be one of the following in approximate order of descending Access: Waterproofed concrete slab, Thatch, Clay roof tiles, Sheet metal, Concrete roof tiles. Other roofing materials like Natural slate tiles or Copper sheeting are available as well but less commonly used and expensive. In South Africa, a double roman concrete roof tiled roof at 26 degree pitch might be one of the most cost efficient roofs. Using sheet metal roofing might add between 20-80% to the cost and a concrete slab or thatch roofing might be as much as three times the cost.
ROOF SHAPE
When designing your home also keep the shape of the roof in the back of your mind. If you are looking at building a double pitch roof, having a lot of unnecessary valleys and ridges as apposed to a very simple roof can work out as much as double for the same area of roof. Thatch roofing, being a lot more of a freeform in its construction, a lot more complex designs can be designed without it being significantly more expensive than as is applicable to a rigid tiled roof. A concrete slab roof might be expensive, but there would be almost no limit to the shapes that can be created in the floor plan, without an effect of the cost. With concrete roofs the size is directly proportional to the cost.
PLUMBING & ELECTRICAL
These two items might be the most overlooked cost items for 1st time home builders. The installation and labour cost of these without the fittings could be as much as 15% of the total building project cost depending of the complexity of the design and number of points for fittings supplied. When designing the bathrooms & kitchen try to place them together as close to the sewer connection point as possible but don’t let this control your overall design.
FINISHING
The choice of finishes in your home would noticeably be the dominating factor in the total project cost. If you are a really cost conscious 1st time builder or perhaps a developer, this is where the most savings could be made, but be careful to take it beyond the point where it starts to compromise re-selling value of the home