# Datum Line For Kitchen Fitting



## jedmc571 (23 Nov 2008)

Hello, 

Someone asked me this today, I thought I could answer it, but then I confused myself during the answer  

When doing the layout for your cabinet start point, you need to establish what height you need to work to, so how do you "easily" do it?

I suggested measuring cabinet, plinth, and finished floor height, and make that the datum........Correct? but then I was asked "what if the floors not level" which I assume most would be.......at this stage I went "Doh"

So the question would be....how do you calculate the floor height, and do you start at the lowest or highest point?

The more I think I've got it, the more I get confused

cheers

Jed


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## matt (23 Nov 2008)

If you're fitting pre-built cabinets of a given height then you need to allow for the depth of flooring and reference from the flooring surface at its highest point to the height of the cabinet plus plinth. Then, as the floor drops away, you have to raise the plinth to make up the gap and maintain the cabinets on a level.

If you worked to the lowest point then you'd end up having to reduce the height of the cabinets the more you move toward the high point.

Easiest way I've found to do this is using horizontal laser on tripod and a tape measure. Once you know the height you're after set the laser at approximately that height, point it at each wall in turn, and then use the tape from the floor and take spot measurements to see where the high and low points are. Don't forget to also take spot measurements along where the front edge of the cabinets will go too (i.e. not just up against the wall).


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## Rich (23 Nov 2008)

How was this achieved before lasers were used?

Rich.


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## BradNaylor (24 Nov 2008)

The first thing I do when I am fitting a kitchen is to draw a horizontal line right round the walls of the room at the height of the top of the base unit carcasses, usually 860mm, working from the highest point on the floor. 

It is well worth investing in a laser level for this, as it makes it very easy to then determine the high point. It can be done with a spirit level however; identify by eye what looks to be the highest point on the floor and draw a pencil line 860mm off the floor around the room using a long level.

Then check that you have started at the true high point using a measure or a length of scrap wood with a mark on it. If you find a higher point on the floor then re-draw your horizontal line starting from there.

All this is very important. I once inadvertantly drew my datum line starting from the lowest corner of the room assuming, as it was a newly built extension, that the floor would be level.

It wasn't!

This made fitting the integral appliances on the opposite side of the room something of a challange. 

Cheers
Dan


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## plug (24 Nov 2008)

I allways check the floor for level first, then check finish floor thicknees to be used if it is not allready fitted, then check what the height adjustment is on any under worktop apliances and where they are located in the kitchen.


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## Karl (24 Nov 2008)

Be aware that if you start from the highest point (and set your datum line at the height of kickboards depth plus unit height) you can run into problems with the kickboard if your floor is significantly out of level. If the floor runs out by, say, 20mm, then the kickboard will be 20mm short of the underside of the cabinets at the lowest point. 

Cheers

Karl


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## phantom of the offcut (24 Nov 2008)

Its also worth noting that with a carcass height of 860mm from floor most! integral appliances have to be adjusted to their max and often require you to fit a plinth to stand them on . I


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## j (24 Nov 2008)

Dan Tovey":ggsmhsqy said:


> It is well worth investing in a laser level for this, as it makes it very easy to then determine the high point. It can be done with a spirit level however



Slightly OT, 
Having never used one of these laser levels, I was just wondering how they actually work. Are they self leveling? or do you have to level the laser by eye (get the bubble in between the lines) I've often had problems using a traditional level and determining if the bubble is exactly in the middle or not. Obviously if I use one of these lasers in the middle of the room, any error is magnified. I'd then think I need to check that it really is level, but wouldn't know how to do that without a good reference to go off.

I guess what I really need is a fool proof way of determining level to within a good tolerance without having to figure out if that bubble is slightly to one side.

Anyway, rant over.
Thanks
J


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## Shultzy (24 Nov 2008)

J, it depends on how much you pay for the level. Mine cost £10 and I level the tripod up, which has a circular bubble, then level the spirit level which has the lazer in the end. The more expensive ones have a spinning lazer which is self leveling.

I leveled my kitchen with reference to the free standing cooker (swimbo wanted the worktops at the same height) as it is on wheels and is non-adjustable for height. I made the kickers out of mdf and covered them with the same material as the floor covering


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## TrimTheKing (24 Nov 2008)

j":23t8vhez said:


> I've often had problems using a traditional level and determining if the bubble is exactly in the middle or not.
> 
> I guess what I really need is a fool proof way of determining level to within a good tolerance without having to figure out if that bubble is slightly to one side.
> 
> ...


At last, one I can answer.

This is the easiest thing in the world. Take a length of clear plastic tube (doesn't matter how long, so long as it's long enough to reach the two ends of the line you want to level) and fill 2/3 with water. Then, when you hold the two ends up, no matter how far apart, the water will always be at the same level at both ends of the tube as water finds it's own level.

:lol: 

Cheers

Mark


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## joesoap (24 Nov 2008)

Rich":1y52mopm said:


> How was this achieved before lasers were used?
> 
> Rich.


We used a water level (a garden hose will do ) . First rule of shopfitting . Strike your datum around all the walls at half the height tween floor n ceiling and all vertical sizes are taken from it . If scribing for floor is necessary so be it , that's what plinths are for , but tlheres a choice these days for some , it's called ........sillicon .


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## Jake (24 Nov 2008)

joesoap":3iug5nfb said:


> First rule of shopfitting . Strike your datum around all the walls at half the height tween floor n ceiling and all vertical sizes are taken from it.



What if the ceiling slopes?


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## joesoap (24 Nov 2008)

Jake":1fhupycp said:


> joesoap":1fhupycp said:
> 
> 
> > First rule of shopfitting . Strike your datum around all the walls at half the height tween floor n ceiling and all vertical sizes are taken from it.
> ...


Well if the ceiling slopes the datum will tell you exactly by how much that's what its there for .


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## Jake (24 Nov 2008)

Sorry, trying to understand this. Do you mean take somewhere in the room, find the half-way point between ceiling and floor at that point, and throw a datum around the rest of the room level with that point?


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## j (24 Nov 2008)

That's so simple it's briliant.

I'll have to keep a length of clear tube in the toolbox.

Thanks
J


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## TrimTheKing (24 Nov 2008)

joesoap":353asc1s said:


> Jake":353asc1s said:
> 
> 
> > joesoap":353asc1s said:
> ...


Hmmm, I'm not sure. If the floor and ceiling both slope by 1' over a 10' run then in theory a worktop run along that line would look level (to floor and ceiling) but be a 1 in 10 slope!?

I fear that I am nt fully understanding your explanation, so if that's the case  

Cheers

Mark


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## Digit (24 Nov 2008)

Laser levels are great for some tasks J, especially fitting gutters for a straight line slope. As leveling devices they are no different to any spirit level of similar length to that which is fitted to the laser.

Roy.


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## Shultzy (24 Nov 2008)

Trim, what Joe is saying is a standard engineering method. The object of the level datum line is to provide a know reference point from which all other points are measure to. For example if you wanted to draw a 3D drawing of your house and grounds you only need to pick one point somewhere on the ground and reference every other point to this datum. This will enable you to construct an accurate drawing, even if this point is above the level of the dpm.


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## Doug B (24 Nov 2008)

Roy doesn`t it take longer to set the laser level up for guttering than actually fitting the gutter?
Having said that i only have a line level so it`s not like i have any other choice  .


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## Digit (24 Nov 2008)

Not in my experience James, no. I've always found with plastic gutterings getting the first and last clip into place for the slope to be simple. It's getting the intermediate ones in a straight line that I have found to so hard. My laser level sorted that problem for me PDQ.

Roy.


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## Doug B (24 Nov 2008)

Roy,
I`ve always strung a line from the center of the first & last clip, then offered each intermediate clip up to the line & fixed it to the facia. This then ensures that even if the facia is leaning in any way, that at least the center of the gutter runs true.
Though as i say not having a laser level leaves me with no other option, interesting to learn how others work.
Always more than one way to skin a cat.
Cheers.


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## Digit (24 Nov 2008)

That is exactly how I used to do it James, but with plastic guttering I find, in a high rain area like this, that unless you are 'spot on', rain water collects in any dips. Now here, my down pipes are 10 mtrs apart, any steep slope runs you down below the facias, any shallow slope tends to be beaten by sag in the string.
Just how inaccurate my string was was shown up by my laser!  

Roy.


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## Doug B (24 Nov 2008)

Looks like i`ll be adding a laser level to my Crimbo list, thing is the list is getting longer & longer :roll:
Oh well just hope i`ve been a very good boy :lol:


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## joesoap (24 Nov 2008)

j":v3b0cz5a said:


> That's so simple it's briliant.
> 
> I'll have to keep a length of clear tube in the toolbox.
> 
> ...


Hi Jake 
Here is some detail . using the water level is normally a two man job but if you get someone to hold one end of the filled level to the mark (usually eye level is handiest )in a kitchen let's say , take your working end corner to corner marking off as you go . Ping chalk line to marks . Your tube has to be filled to overflowing to expel air bubbles . I suppose there are someone somewhere on line that has videoed the procedure . No doubt like video has killed the radio star so it be with the trusty water level and laser . However a datum can be struck with a stabila and a goodeye . But ! it's not a datum . Cheers !


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## Mr Ed (24 Nov 2008)

Well I use an optical level (what some would know as a dumpy level) but only because I have one from the day job. Its a bit over the top for kitchens and bathrooms but I have the most accurate floor tiling in the county!

Cheers, Ed


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## joesoap (24 Nov 2008)

EdSutton":29kend5d said:


> Well I use an optical level (what some would know as a dumpy level) but only because I have one from the day job. Its a bit over the top for kitchens and bathrooms but I have the most accurate floor tiling in the county!
> 
> Cheers, Ed


A'hhh the dumpy level , now that's goin upmarket that is . There's something to be said for the day job when it comes to tools and the odd stick(nudge nudge , wink wink ) and here's me thinking I've joined the silver shedders . Cheers !


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## chippy1970 (24 Nov 2008)

A datum is just a level line to work from, the datum line could be at any height but I usually put one roughly half way between where the base units and the wall units will be, I suppose around 1100 off the floor.

You can then work all the other measurements off your datum.


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## Mr Ed (24 Nov 2008)

As an unwritten standard on most UK construction sites we would put a general datum level 1.0m above finished floor level. That usually seems to suit most trades.

Cheers, Ed


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