Every building project starts with good foundations and we dont just mean the lowest part of the structure that spreads the load of a building!
It is essntial that the designs are based on accurate as built measured survey drawings, weather it be a full measured building survey or a topographical land survey they must be clear, detailed and accurate in order for it to be a problem free design & build.
In this blog post we will cover:
- How is a measured survey carried out?
- How is a topographical survey carried out?
- How long does it take to carry out a measured survey?
- How can I tell if I have a trusted surveyor for the job?
- How much do measured surveys typically cost?
- How can I make sure I get the best price for my measured survey?
- Get a quote
A measured survey can be undertaken in a number of ways using a wide variety of measuring tools. Generally you need a measured building surveyor to undertake a measured survey. They will accurately measure using a tripod with 1 of 2 things, A 3D laser scanner (preffered for speed and acuracy) or a total station (preffered for Topographical surveys and ground control). They should also have a disto laser distance measurer and a traditional tape measure as a minimum. The will go around the outside and inside of your property moving the tripods around and taking measurements / scanning the building. Whilst they are doing this they will also be taking hand notes for distance and height verifications that will be written on to a roughly drawn floor plan on paper. Once they have got all the measurements they need, they should create a backup copy of their data before leaving to go back to the officeas good practice.
How is a Topographical survey undertaken?
A surveyor will turn up to site with a GNSS RTK reciever this is essentially a device able to give a few mm accurate positions and heights of a single point, a good surveyour would place 3 ground control points and measured these in with the instrument, taking hundereds of measurements and giving an accurate average of the points. These ground control points vary on the site, if its a road you would use Hilti nails and a marker, this is essentially a nail with an inverted point in the center for a detail pole / gps pole to be placed accurately in the center of it every time.
Once they have the coordinates they would add these into a robotic total station using eastings, northings and elevations. they then set up the instrument using these positions to establish the machines position and height on its tripod. They take all the measurements needed from that position and then move to another position and repeat the steps until they have covered the whole survey area.
- Kerb positions & heights
- Surface changes
- Road markings
- Surface types
- Building walls
- Landscaping walls
- Roof positions & heights
- Chimney positions & heights
- Tree positions, diameters of trunks, canopy spreads & heights
- Manhole / inspection chamber positions with cover & invert levels
- Street furniture
- overhead phone / power lines
- spot heights
How long does a measured survey take to carry out?
Its a tricky question, as some house layouts are really simple and others are more complex, however, a good surveyor with good up to date equipment should be able to carry out a measured survey of a 3 bed detached house in around 5 hours.
Topographical surveys would take around the same time, you have less to cover but normally use manual total stations so rather than collecting millions of points a minute like a laser scanner, your capturing one every time you ask it to record a point.
How can I tell if I have a trusted surveyor for the job?
We would recommend you check the below
- Google reviews
- Drawing examples of previous jobs
- communication – if they come back to you promptly and ask lots of questions, you have a good chance to be treated well throughout the entire process and recieve good communication throughtout aswell as good aftercare
How much do measured surveys typically cost?
It varies on the company, the propery and the location. we always recommend you gather 3 quotes and compare the information they give you and asses how professional they are when dealing with them. A cheaper price shouldnt be the first thing you look for!
A quote would be generated on an estimation of time, travel expenses, equipment, software use and labour, so every job is different.
At Bidston Draughting a rough idea of costs can be found below
- 3 Bed house – floor plans only – Inside of London – £800
- 3 Bed house – Floor Plans & external elevations – £1100
- 3 Bed house – Floor plans, Sections & external elevations – £1300
- Single plot house Topogrphical survey – £1250
At Bidston Draughting we do not charge VAT so you already make a fantastic 20% saving as a homeowner!
Please get in touch for an accurate quote today!
020 3576 1705
How can I make sure I get the best price for my measured survey?
Speak to your Architect, Designer or Engineer and get a full specification of what as built information is needed for their designs.
Its easy to just ask for the world, but when you only need a fraction of it you are wasting money, if a surveyor uses a 3D laser scanner to undertake your measured building survey, extra drawings can always be added down the line without the need to revisit