Scottish Slates - Suggestions?

[FraserClarke]

I'm scratch building a goods shed/warehouse for my Scottish dockside layout, but struggling a bit with the slates. The building is based on fuzzy photos of the prototype, filled in with imagined detail borrowed from other similar style buildings. The roof is of Scottish slate, which is quite a bit 'rougher' than the usual stuff found further south. The slates themselves are smaller (typically 4-10"), thicker (guess 0.5"+), and with much rougher edges than "normal" slate. The slates tend of get smaller towards the ridge line. It's quite a distinctive look, which I'd like to try and recreate.

 

Below is a image of the style of building I'm going for. This is a 'modern build' (I remember it being built at Bo'ness in the early 1990s), but of a traditional style. 

 

 

My attempts so far have been based on scoring the tiles into thin strips of card, sticking the strips on in the usual way, and then painting with acrylics (colour not quite right yet, bit too Welsh!). Was fairly happy with the first attempt (back of the knife), but looks too much like neat 'normal' slates. Second attempt (scoring with a blunt scribing tool) looked great before it was painted -- but as soon as the paint went on the damaged fibres on the score lines all stood up and looked rubbish...

 

 

Any suggestions on how I might achieve the rough - but not too rough - edge to the tiles would be much appreciated!

 

Thanks in advance!

[Daddyman]

It seems your troubles are coming from your attempt to make life easier - that is, by scoring the tiles into strips so as not to have to cut them individually. It seems to me the solution is either: (1) using something different to score with (or a different material to score in); or (2) following what Dave Bradwell said in an old MRJ - do it the way the prototype does it: in this case, that would mean cutting and shaping the tiles individually. 

 

Good luck either way. 

 

Good to see there's another Scottish modeller condemned to live in Oxfordshire, by the way! 

[Dava]

It doesn't look too bad, if there will be a 'back' or less seen side to the roof then do that first. Use narrower rows as you go up the roof. The color looks OK prior to weathering. I'd keep going and finish it.

 

Useful article on Scottish slate here: https://britishslateforum.wordpress.com/2011/02/28/scottish-slate/

 

Most Scottish slate cam from West Highlands quarries such as Ballachulish and Easdale [fascinating place] but much was imported from Wales.

 

Important difference from many English buildings was [and is] that Scottish slate roofs are laid on a solid planked wood surface, partly as the weight is heavier, so the roof is unlikely to distort with age. Suggest looking at actual buildings of the era and photographs.

 

Hope this helps.

 

Dava

[Stubby47]

One idea to try would be cut the slates into rows, as before, then stack the rows together and distress the bottom edge(s) with a needle file.  Discard the bottom strip (as this will be the most damaged).

 

Randomly place the strips on the roof so the same file marks are not adjacent.

 

HTH

 

Stu

[katwigan]

Hi, Are you sure that the slates actually get smaller towards the ridge line, or is it a matter of perspective making it appear as such?

 

 As an alternative to Stubbies needle file to 'distress' the edge of the card, this little tool is something that the ladies that come to my wifes card making sessions all appear to have to distress the edge of the card. I will have to get back to you on it's effectiveness on roof slates. ( I have several sections of roofing to do but hadn't actually thought of distressing the bottom edge.)

 

 

If you are not happy with painting the slate have you considered printing out a suitable photo of slates and cutting that up into strips. 

This is a photo that I have just put together as an example ,( doubled in length, by copying, and pasting a mirror image onto the end of the original after correcting the perspective a bit )

 

 

Or the other option using something like Scalescenes roofing slates, again this is one I was already fiddling with . The rows of two slates is such that the top row of one piece is the bottom row of the the next one up ( If that makes any B.. sense at all, I know what I mean anyway )

 

 

And then stuck down as per the method you are already using to produce

 

 

Just a couple of thoughts anyway

 

Kevan

 

 

 

 

[Job's Modelling]

For a good choice of slate roofing have look at https://www.textures.com/browse/slate/2130 

I used some of their textures before, with a good result.

 

For a more rough look you could print them on textured (photo) paper.

[flubrush]

I did a Scottish style slate roof in 7mm on a goods shed.  It was the subject of a thread in another forum

 

http://www.westernthunder.co.uk/index.php?threads/slating.1979/

 

...and I think you have to register to see the pictures.   There are some links in that thread to article on slating.

 

The method of building was to cut individual slates from Plastikard sheet and bevel and colour them before laying them on the roof,  with proper sarking.   It was a labour of love and took for ever.  :-)   But it did ressemble the slightly rough and ready looks of the average Scottish slate roof.  The slate sizes were graded from large at the bottom to smaller at the ridge.  Not all Scottish roofs were rough.  I do remember a large house opposite my house in Vale of Leven which had a superb Ballachulish slate roof with smooth and beatifully cut slates all over.   When they pulled the house down to make way for a bypass I couldn't make use of the slates since they were too good for my more average quality roof. :-)

 

Here's one pic of the shed roof nearing finish.

 

 

Jim.

Edited August 15, 2017 by flubrush

[FraserClarke]

Thanks very much for the replies. Certainly lots to consider.

 

do it the way the prototype does it: in this case, that would mean cutting and shaping the tiles individually. 

 

Indeed, I have considered that ; but ROM esimtate is >10,000 slates... so I think I need to compromise somewhere in order to get it done at all!

 

Important difference from many English buildings was [and is] that Scottish slate roofs are laid on a solid planked wood surface, partly as the weight is heavier, so the roof is unlikely to distort with age.

 

That's a good point which I hadn't considered. Perhaps I need to rethink my base structure of cereal packet card -- I'd been thinking a bit of natural distortion would look OK, but maybe not!

 

Hi, Are you sure that the slates actually get smaller towards the ridge line, or is it a matter of perspective making it appear as such?

 

 As an alternative to Stubbies needle file to 'distress' the edge of the card, this little tool is something that the ladies that come to my wifes card making sessions all appear to have to distress the edge of the card. I will have to get back to you on it's effectiveness on roof slates. ( I have several sections of roofing to do but hadn't actually thought of distressing the bottom edge.)

 

Thanks, that looks like an intriguing device! I'll have a look in craft shops.

Yeah, the slates really do get smaller; 'diminishing courses' it's called I believe. As Stu said, pretty easy to do by cutting thinner strips.

 

I did a Scottish style slate roof in 7mm on a goods shed.  It was the subject of a thread in another forum

 

http://www.westernthunder.co.uk/index.php?threads/slating.1979/

 

Well now, that's just devastingly good... It really does show the benefit of treating each slate as a slate.  I note you mention you have 60 scale ft of roof and it took 'a while'. I think I have some 500 scale feet in effect (multiple pitched sheds), so I just don't think it's feasible for me unfortunately

 

Should have mentioned I'm working in 4mm here.

 

Seems like I need to press on my roughly my current approach, and try some different techniques for distressing the edges. Also thought last night of using my kid's playdoh pizza cutter, which has a fairly sharp plastic edge to it. That might do the trick of compressing the edge rather than ripping the card... I've also bought some dark grey card, which I hope means I'll need to use less paint to colour/weather it, which might help it from 'blowing'...  I did consider using textured prints (rest of the building is scalescenes brick), but I think this is one area where a bit of exaggeration of the real thing works and the texture would look a bit too flat.

 

Will experiment and report back!

[flubrush]

 

Well now, that's just devastingly good... It really does show the benefit of treating each slate as a slate.  I note you mention you have 60 scale ft of roof and it took 'a while'. I think I have some 500 scale feet in effect (multiple pitched sheds), so I just don't think it's feasible for me unfortunately

 

Should have mentioned I'm working in 4mm here.

 

 I can't remember exactly how long it took,  but it did take a long time.  The actual slating of the roof wasn't too bad - it was cutting all the different sizes of slates and bevelling them which took the time.  I have had thoughts about how strips of slates might do the same job but getting the result to be truly random would be difficult.

 

There's also a question of quite how random the slates on a roof might be since a slater might have tended to select piles of slates of the same width and height to work on an area to cut down on the fiddling that might have to be done to get the overlaps acceptable.  When working on my old slate roof. (ex church manse circa 1860) I got the feeling that a fair bit of the random factor was caused by repairs over the years with whatever slates were handy. :-)

 

Jim.

Edited August 17, 2017 by flubrush

[Portchullin Tatty]

My technique is to use relatively light paper - photocopier paper - and prior to starting I spray it with a variety of car aerosols and enamel paints.  These are applied liberally so that they soak through the paper thickness and effectively bind it all together as one.  By using a variety of colours there is a very very slightly inconsistency that when applied takes the uniformity off the slate colours.

 

Then, I use a sharp scapel blade to cut the joints between the tiles for about two thirds of their length.  I don't cut the final third as the objective is to create long strips of tiles that have the joints at their bottom but are united at their tops.  Once this is done - and it is a laborious process - I cut them into strips and affix them with spraymount.  I try and make the cuts as consistent a possible safe in the knowledge that I won't succeed and the slight variation adds realism.  I then wash colour on top of the laid slates to add a little more variation to the colour and to show water runs/weathering.

 

The combination of sealing the paper and using a sharp scapel means I do not have any problems with the fibres being apparent when the paper is cut.

[FraserClarke]

Work has been 'hectic' to say the least for the past few months, so very little progress. I've tried out a few options in odd free hours here and there when I really can't face going through my 6th 100+ page document of the day...

 

Best I've got so far is based on Mark's suggestion of painting the paper then cutting. This is similar to what I did on my first attempt, but I just scored the "inter-slate" lines rather than cutting each one out. I thought the score would be wider, and hence more noticeable -- but it seems not. The paper was first painted with a mix of acrylics and grey emulsion as a base, and then marked and cut (all 4mm here, for ease of testing) once dry.

 

 

Fairly happy with how this piece has come out. Edges of some slates are poked and roughed up with a knife after installing.  The shine is from a slight excess of PVA, but it is meant to be Scotland so they are probably wet anyway. I still need to put an overall wash on to tie things together and add a bit of weathering, but pleased with this so far... Probably needs a bit more attention to reducing slate size as I go up the roof.

 

 

Work should calm down in a few weeks time, so will perhaps get the rest of this roof slated, 'flashed', and weathered to see what the final effect looks like...

 

PS -- I did try putting on individual slates; not as tedious as I'd thought, but my model slating would do a gross dis-service to the roofers of old!! Hard enough getting the strips to look vaguely straight :-\

[Portchullin Tatty]

A couple of suggestions to assist:

 

- use spray mount to the underside of the slate strip.  This remains tacky after it is applied and it will enable you to move them around until you get them in the right location and then to "press them home" to affix them.  I found this overcame any tendency for the paper to peel up.

 

- make sure the paint fully saturates the paper (and is a cellulose or enamel).  This will seal the paper and stop the prospects of any furryness appearing

 

- follow the prototype and use double lapped slates - they are easier to handle on the model and will get the feel of the slope right.  A good diagram of double lapping can be found here or by googling

 

- remember the possibility of using a bit of a wash at the end to bring the colours together - (the wash should be close to transparent, it is not really there to colour, just bring the colours together)

 

But I do think your roof if beginning to look real (and I am a professional in this regard!).  

 

Do some research on how leadwork and other detailing works around abutments, hips, chimneys etc; this will also help.  If you really want to get into this, find some old "Mitchells Building" book (volumes 1 & 2 are best and don't be scared of getting really old ones, we have not changed how we do it for a long time!).  Sometimes these are expensive but sometimes you can pick them up for a £5 each as loads of surveyors, builders etc had them as they went through college.

 

And one final thing, responding to an earlier point someone raised.  Some buildings do have larger slates at the eaves which reduce in size as they go up to the ridge.  This is not, however, universal and tended to be reserved for large or prestigious buildings.  Thus, for most small railway buildings it would be unusual.

 

Good luck!

 

 

 

Mark

Edited September 20, 2017 by Portchullin Tatty

[Damo666]

Hi, Are you sure that the slates actually get smaller towards the ridge line, or is it a matter of perspective making it appear as such?

This is quite normal with vernacular buildings. I think the reason was that the slater (a craftsman as opposed to a basic roofer) would be selecting the slates on the building site and grading them by size.

 

Considering that they were using a natural material, how they split (being a sedimentary stone) would vary due to imperfections and fissures in the material, and less because of a lack of skill. You then ended up with a pile of slate split into the ideal slate size, but as you cut them down to rectangular shapes having nice parallel edges some would crack or break. Instead of chucking the smaller pieces away you kept them aside and then re-worked them into smaller rectangular sizes. As you use up the largest slates first you then move onto the next smaller size, and so on as you work up the roof.

 

Cannot believe it was due to weight on the roof, as the amount of slate would be about the same / ft² of area, but with more overlaps and more nail fixings. I’ll have to think about that.

 

This was taken at the harbour in Tenby. You’ll see similar grading of the roofing tile in the Cotswolds but using a thicker stone instead of slate. It’s whatever was available nearby and then worked on site to the shape.

[flubrush]

Considering that they were using a natural material, how they split (being a sedimentary stone) would vary due to imperfections and fissures in the material, and less because of a lack of skill. You then ended up with a pile of slate split into the ideal slate size, but as you cut them down to rectangular shapes having nice parallel edges some would crack or break. Instead of chucking the smaller pieces away you kept them aside and then re-worked them into smaller rectangular sizes. As you use up the largest slates first you then move onto the next smaller size, and so on as you work up the roof.

 

This is basically what I had found out when I researched Scottish slate roofs.   For everything but the top quality buildings,  the slater worked with what he got delivered on site and part of the job was sorting out all the different sized slates he had.   Starting large and going small as you go up the roof makes sense to keep wastage down.

 

Jim.

[Portchullin Tatty]

This is basically what I had found out when I researched Scottish slate roofs.   For everything but the top quality buildings,  the slater worked with what he got delivered on site and part of the job was sorting out all the different sized slates he had.   Starting large and going small as you go up the roof makes sense to keep wastage down.

 

Jim.

 

Whilst lots of horrid things go on on construction sites, so I dare say that there will be examples where this is true and "just happens" the use of different slate sizes is normally by design.  

 

Slates, whether welsh slates or from elsewhere (many slates in Scotland are from Ballachulish) are cut as the leave the quarry not when they get to the work site.  Cutting slates to size is a skilled job and the wastage (ie unintentionally broken) slates from letting even a roofer that can do it would be so high as to make uneconomical to do it on site.  They would trim some slates to suit the circumstances, but as a rule the use graduated slate sizes is not accidental.

 

There are a whole range of recognised sizes that the slates are formed to and you can buy a selection of sizes to suit the job that you have in mind.  A bit more on this and also the history of where these names came from can be found here.

 

As I said earlier, graduated slate sizes does occur, more so (but not exclusively) on large or prestigious buildings, but is not universal.  So you takes your choice!

 

 

 

Mark

[MikeHohn]

During colonial times in New England, a frequent practice with wood frame houses was to graduate clapboard siding with narrowest boards at the top. Sometimes very subtle. It was a deliberate design element.

[FraserClarke]

Been making slow progress with this amongst work, home and other commitments. I've got two of the three roofs for the first of my buildings done now. I’ve pushed on with the painted paper, made into strips of slates with partial cuts between each slate.  It doesn’t quite get the rough edged effect I was looking for – but overall I’m happy with the look. There is the odd wavy line around, but I think I can live with it!   I’ve spent a lot of time looking at old slate roofs in Edinburgh over the past few months, and there are certainly enough prototypical examples to justify pretty much anything you want!   

 

 

I used acrylics to paint the paper, rather than the enamels Mark recommended – simply because I don’t have any enamel/cellulose sprays and wasn’t prepared to buy a range of colours just for this.

 

The leadwork is from scalescenes, but seems to match quite nicely. I made the strips a bit too wide I think, but acceptable from distance at least!

Next step is to add some weathering and washes. The weathering on the real thing always looks surprisingly strong to me, so this is probably a case of not scaling down what you see 1:1 (or 1:76) for fear of it overpowering the scence…

[Marly51]

We had our croft house roof re-slated a few years ago and was aware of the diminishishing size of courses in traditional Scottish and Welsh buildings . A friend whose work involves conservation of buildings in the Snowdonia National Park confirmed this and I found this link http://www.buildingconservation.com/articles/scottish-slate-roofs/scottish-slate-roofs.htm which mentions that slates of differing size were utilised to maximise efficiency of quarry output.

Edited December 31, 2017 by Marly51

[Silver Sidelines]

I always thought that the courses diminished in size for a very good technical reason, the smaller slates were less likely to lift in high wind (aerofoil effects).

We had our croft house roof re-slated a few years ago and was aware of the diminishishing size of courses in traditional Scottish and Welsh buildings . A friend whose work involves conservation of buildings in the Snowdonia National Park confirmed this and I found this link http://www.buildingconservation.com/articles/scottish-slate-roofs/scottish-slate-roofs.htm which mentions that slates of differing size were utilised to maximise efficiency of quarry output.

We have a modern Scottish Slate roof with 'big' slates for all the courses - and we know about slates lifting -because we get lots of wind (gales)!

 

Ray

Edited December 31, 2017 by Silver Sidelines

[Marly51]

I always thought that the courses diminished in size for a very good technical reason, the smaller slates were less likely to lift in high wind (aerofoil effects).

 

We have a modern Scottish Slate roof with 'big' slates for all the courses - and we know about slates lifting -because we get lots of wind (gales)!

 

Ray

Hi Ray,

It is a while since I had the conversation with my friend in Wales - will check this out. Our new roof was built with the regular large slates and another feature of the Scottish house subjected to high winds is that the overhang at the eaves is minimal, just enough to throw rainwater into the gutter. We have skewed gables which is the other main feature that prevents wind and water lifting the slates. I have a great little reference book in my collection, which has useful information when scratchbuilding traditional Scottish Buildings. Published in 1975 by Famedram - the odd copy may be still available second hand.

[Silver Sidelines]

Thanks Marly

.. - will check this out. Our new roof was built with the regular large slates and another feature of the Scottish house subjected to high winds is that the overhang at the eaves is minimal, just enough to throw rainwater into the gutter. .

Chinese slates, paving slab skew stones and original 1840s sandstone ridges


Yes Skew Stones (paving slabs), ancient sandstone ridges and new Chinese Slates!

Eaves are a sore point. We were required by Building Control to have a continuous ventilation strip around the eaves. Because of our location and the force of the wind we get snow and rain ingress 'up' through the strip. We also think it allows our mice in!  Not long after I noticed new houses were being built with 'green' breathable felt - might have been a better solution had it been available
 
Ray.

Edited January 2, 2018 by Silver Sidelines