Pre Construction of a landed house - Considerations and Questions

[leechaorui 2]

Does anyone know how much it cost to do the pre construction soil test and topography survey fee to plot out the exact perimeter of the house?

Edited October 14 by leechaorui

[snoozee 98]

Go hire an architect and let them arrange for you. The soil investigation needs to have instructions from a PE on what to do and this is not what a layman can scope out.

topo survey needs to have cadastral map downloaded from SLA INLIS and additional plans purchased on INLIS as well so a QP will know what needs to be purchased and provided to the surveyor and the soil investigation team.

I did both together for about 5K+ some years ago. Yours would likely cost more due to inflation as well as maybe additional holes need to be bored for the soil investigation due to bigger plot of land. Anyway below are the companies I used back then.

soil investigation - ABV

topo survey - CAK & FG Survey

[flai 0]

We did our soil test early last year, was about $4k, and topo survey two years ago was about $2k. 

[leechaorui 2]

On 10/16/2024 at 7:40 AM, snoozee said:

Go hire an architect and let them arrange for you. The soil investigation needs to have instructions from a PE on what to do and this is not what a layman can scope out.

topo survey needs to have cadastral map downloaded from SLA INLIS and additional plans purchased on INLIS as well so a QP will know what needs to be purchased and provided to the surveyor and the soil investigation team.

I did both together for about 5K+ some years ago. Yours would likely cost more due to inflation as well as maybe additional holes need to be bored for the soil investigation due to bigger plot of land. Anyway below are the companies I used back then.

soil investigation - ABV

topo survey - CAK & FG Survey

Thank you snooze.  My land is rectangular in shape.  I thought that soil test is a standard test of boring 2 holes, front and back and this report is good enough for almost all kinds of design for landed house.

[leechaorui 2]

On 10/16/2024 at 10:01 AM, flai said:

We did our soil test early last year, was about $4k, and topo survey two years ago was about $2k. 

Thanks.  $6k to $7K for both works is about the market price.

[snoozee 98]

On 10/17/2024 at 3:41 PM, leechaorui said:

Thank you snooze.  My land is rectangular in shape.  I thought that soil test is a standard test of boring 2 holes, front and back and this report is good enough for almost all kinds of design for landed house.

how many holes depends on what the PE requires of which land size also plays a part. mine only did one bore hole

[leechaorui 2]

On 10/18/2024 at 4:25 PM, snoozee said:

how many holes depends on what the PE requires of which land size also plays a part. mine only did one bore hole

Thanks snooze.  Would like to check on the following questions:

1.  Is there a land betterment or development charge to build a detached house from a semi detached house?

2.  Is the balcony spaces created considered as part of GFA by BCA/URA?

3. Can the water tank and pump be placed on top of the home shelter? Can the home shelter be placed at the wet kitchen area?  The height for first floor is expected to be about 4.3m. 

[snoozee 98]

no development charge for private dwelling if convert from semi-d to detached. but you need to ensure your neighbour's plot of land can also qualify as a detached house before you can convert yours.

no GFA limit for private dwelling.

not sure what kind of water tank and pump you are referring to. if your house will be above the min height requirements for water tank, normally water tank will be placed on the roof top (gravity flow) and pump on the ground floor. it doesn't make sense to have the tank in the middle of the house since you may need an additional pump to push the water from the tank to the top floor.

There's specific requirements on where the HS can be located from the boundary as well as the size (height and internal volume) of the HS. height limit is between 2.4m and 3.9m based on your first floor height of 4.3m, your HS must be located more than 7m from the boundary line. your architect should know the regulations and advise you better on where the HS can be placed within the house. Don't try to push the regulations for HS as you will likely to be asked to do rectifications (whether inside or outside) to comply with the regulations as BCA will send an officer down to inspect the HS before you are even allowed to apply for TOP. Get your QP to submit the HS design for clearance at the start so you know you are safe and don't end up having to do rectification works after the inspection. The worst nightmare is you may be asked to hack down the entire HS and relocate it to another location in the house to comply with requirements.

[leechaorui 2]

Does the QP submit the whole house design for clearance or the QP submit in parts such as HS and other part of the house design in separate tranches to URA/BCA?  For the house design, is it normal to leave a bigger setback at the side and the back of the house so that cars could be driven to the backyard of the house for parking there?  Understand that it is common for people to park their cars in the front car pouch of a landed house.   What is an appropriate side setback and backyard setback?  The house is about 14.1m in width at its narrowest point.   

[snoozee 98]

your QP has to submit the entire house design to URA for approval first. BCA approval is also needed with structural designs for new house and demolition plan from the PE. Some QP don't submit the HS plans to SCDF for approval initially and while this is not wrong, if there are issues with the design rectification work will be problematic. That's why I mentioned to get the QP to submit for HS approval at the start as well. If your house is going to be physically more than 3 storeys, then need to submit plans to SCDF for fire clearance as well.

Standard minimum setback for houses is 7.5m at the front and 2m for the rear and sides. For detached houses, you are allowed up to 50 percent site coverage for houses outside GCB areas which means you will have bigger setbacks in order not to exceed the allowed site coverage. The appropriate setback is based on your own needs and you are allowed to have bigger setback if you want as long as the minimum is met.

[leechaorui 2]

Thanks for the tip to get early design clearance for HS.  I am planning to use about 25% of the land to site the house building.  Will leave a bigger space at the backyard for gardening area, car parking or a future swimming pool etc..  

You triggered me to think about fire safety aspect.  Do you think it is better to site the lift away from the stairways or should they be sited next to each other?  Thinking about potential fire impacting the lift and people would have to use the stairs to get out.

For GFA area of about 6000sqft for a small family, with mostly outdoor garden space, do you think it is necessary to install central airconditioner unit to serve all areas or each room should be fitted with its standalone airconditioner?  What are the pros and cons?

To design a house that is sustainable and fairly maintenance free, what other considerations should one include into the design? 

Thinking of designing the house as a wheelchair friendly smart home and one that hardly need maintenance such as installing micro cement to make the walls paint free, use of homogeneous tiles and man made wood instead of natural wood and stones (except for mandatory maintainence such as lift servicing and probably yearly termite treatment.)  

Is it good to design the ensuite rooms to be sufficiently self containing such as installing a pantry, a small living cum dining area, walk-in wardrobe, king size bed area, area for zoom or remote work, a washing area for clothes, etc.. in the bedroom?  Got the idea from Presidential Suite bedrooms.  Not sure if 700sqft inclusive of balcony space for each standard room is enough.

 

[snoozee 98]

since you have space to play around with, you can locate your lift wherever you want. The lift core itself is supposed to have its own air vent at the top and if you build a concrete lift shaft, it should be able to contain any fire/smoke for a while to allow for occupants to escape. Anyway smoke alarms are mandatory for all new developments so this will serve as the early warning should any fire breaks out within the house.

Whether to do central aircon or individual units is up to your own preference. Just note that for central aircon, should the condenser breaks down, all will be affected compared to having individual units. I heard that VRV central systems is more energy efficient but I can't confirm.

There's no such thing as maintenance free. The keyword should be ease of maintenance. If you want to be fully accessible, then design it with ramps where there's a drop in level. Some locations will have to have a drop in level (eg: wet kitchen) to allow for washing so instead of a hard step, incorporate a ramp instead. But in order to add ramps, you need a larger space so that the gradient of the ramp is more gentle. For toilets, you can design it to be level except for the shower area where there's just a minimal drop to prevent water flowing out. Try not to use homogeneous tiles for first storey as there will be temperature variations due to proximity to actual earth and the tiles may crack. My friend's house used large format tiles in the living room and cracks had appeared in many pieces of tiles. That's why I decided to pay more for actual marble to prevent such issues from happening. if you can live with cracked lines on the walls, then you can keep the walls paint free. Even painted walls will develop cracks as the house settle down after some time but at least can use paint to cover up.

700sqf is like a HDB 3 room flat size so you can design your house in this manner if you want. There have been designs where a single house is "split" into distinct "units" for different families staying in the same house. But take into consideration how workers need to move the bulky items up to the upper levels. So either you buy smaller fridges/washers or make sure your lift is big enough and your staircase is wide enough to move up the king size beds.

[leechaorui 2]

Will take note of the tile breakage issues on the first floor.  I am quite reluctant to install marble because marble tend to soak up coffee/tea resulting in a stain.  Is there any other type of tile that is durable and do not soak up liquid to cause staining?  

Was initally thinking of installing a glass lift.  Probably concrete is still a better option as it would be a lot more durable.

The standard Master bedrooms should have small fridges.  I think should be ok to bring up to the rooms.  For the Master bedroom at the attic, it wil be about 1200sqft.  For that, I am thinking of installing a sauna room in addition to the facilities of the normal standard room.  Is 60A power sufficient or I need 100A power?  Will probably need to have a car charger in the backyard of the house and a charger at the front car pouch area.  

Not sure if there are other areas that need high electricity consumption points.  What other things do you think should be installed or included in the house design.

 

[snoozee 98]

you can get contractor to apply sealer to the marble after polishing to mitigate the stain issue. As long as the spill is not left for a long period before wiping away, it shouldn't cause staining. For light stains, there are ways to lighten or remove the stains. But cracked floor tiles are more problematic than stains.

3 phase 100A supply should be more than enough for any house unless you are running a data center doing crypto mining 24/7.

You may want to consider building a small shed to store the swimming pool pump, balancing tank, etc. It could double up as storeroom as well.