File:Small Roof - mistake.JPG

2013-04-25T09:16:24Z

Roundhouse Architecture:

File:Wire marking courses.JPG

2013-04-25T09:12:16Z

Roundhouse Architecture: Wire marking courses

Wire marking courses

File:View up roof from eaves.JPG

2013-04-25T09:11:39Z

Roundhouse Architecture: View up roof from eaves

View up roof from eaves

File:Small Roof.JPG

2013-04-25T09:11:03Z

Roundhouse Architecture: Small roof

Small roof

File:Shoulder cut mark.JPG

2013-04-25T09:09:40Z

Roundhouse Architecture: uploaded a new version of "File:Shoulder cut mark.JPG"

Slate - course 2 small roof (sr) with mark for shoulder cut

File:Main roof 7.JPG

2013-04-25T09:08:19Z

Roundhouse Architecture: Main roof 7

Main roof 7

File:Main roof 5.JPG

2013-04-25T09:06:34Z

Roundhouse Architecture: Main roof 5

Main roof 5

File:Main roof 4.JPG

2013-04-25T09:06:12Z

Roundhouse Architecture: Main roof 4

Main roof 4

File:Main roof 3.JPG

2013-04-25T09:05:45Z

Roundhouse Architecture: Main roof 3

Main roof 3

File:Main roof 2.JPG

2013-04-25T09:05:12Z

Roundhouse Architecture: Main roof 2

Main roof 2

File:Main roof 1.JPG

2013-04-25T09:04:47Z

Roundhouse Architecture: Main roof 1

Main roof 1

File:First slates straight to curved 2.JPG

2013-04-25T09:04:04Z

Roundhouse Architecture: First slates straight to curved 2

First slates straight to curved 2

File:First slates straight to curved.JPG

2013-04-25T09:02:20Z

Roundhouse Architecture: First slates straight to curved

First slates straight to curved

File:First slates main roof.JPG

2013-04-25T09:01:42Z

Roundhouse Architecture: First Slates main roof

First Slates main roof

File:First slates 2.JPG

2013-04-25T09:00:50Z

Roundhouse Architecture: Overall view of building from other side

Overall view of building from other side

File:First slates 1.JPG

2013-04-25T09:00:02Z

Roundhouse Architecture: Overall view of building showing first slates

Overall view of building showing first slates

File:Snall Roof - mistake.JPG

2013-04-25T08:41:01Z

Roundhouse Architecture: Nailing mistake on small roof

Nailing mistake on small roof

Conical roof slating

2013-04-25T08:39:37Z

Roundhouse Architecture:

File:Slate marking template 2.JPG

2013-03-11T22:57:30Z

Roundhouse Architecture: uploaded a new version of "File:Slate marking template 2.JPG": Tapered template used for marking each course of slates

Image showing tapered template used for marking each course of slates

Conical roof slating

2013-03-11T22:19:50Z

Roundhouse Architecture:

This article is currently under development

'''Traditional Skills - Slating a Conical or Turret Roof.'''

As with any traditional skill or discipline, taking care and time to prepare properly is essential and slating a conical shaped roof or turret using second hand Welsh slates is no different.

'''Roof geometry calculation.'''

It is important to consider the geometry of the surface to be slated which will be a sloping and curved surface or plane. Any natural slate is flat and the sizes available in second hand or new Welsh slate or any other slate will vary. Therefore consideration has to be given as to how a flat surfaced material will fit or sit on a curved plane.

In this article, as a recently constructed example, the roof referred to has a diameter at eaves\gutter level of 8500mm and a roof pitch of 40 degrees. The dimension from eaves to apex on the sloping line of the roof can be calculated by simple geometry. This dimension is important in the setting out and template making procedure.

Next the circumference of the roof is calculated, again using standard geometry. Note – Allowance must be made for any overhang into the gutter at eaves level, in this calculation.

'''Slate selection and grading.'''

The size or width of slate available for the eaves course is checked and it is best to use as wide a slate as possible as the slate widths will diminish in size towards the apex. Also important to ensure the largest size slate chosen will lie properly on the roof round the eaves course. The smaller the roof diameter the smaller a slate width may be required.

Once the size of slate for the eaves or starter course is decided the number of slates required to go round the circumference is calculated. This may not work out to an exact number of slates or slate width, therefore choosing the next round number up the circumference is then divided by the total number of slates. This is important to ensure each slate on each course all the way from eaves to apex, are the same width at the bottom of the slate on each individual course.

For example, all slates on the eaves course should have the same base dimension, just as the slates on any other course going up the roof will all have the same base dimension for that course, and so on.

Before any work is carried out on slate marking or cutting, an approximate calculation of the total number of slates for the entire roof is required.

There are several reasons for this – If the finished roof is required to have a graded appearance ie with thicker slates at the eaves gradually getting thinner towards the apex, all the slates have to be graded into say ‘thicks’, ‘middles’ and ‘thins’ – there may also be other thickness’s in between. By looking at the thickness of the slate and feeling the weight, the grading process becomes easier.

Add to this, the size selection as wider slates will be used on the first few courses and then to save cutting or wasting slates, narrower sized slates can be used higher up the roof.

Grading and sizing the slates is a time consuming job and also requires space to set out the various racks of slates to keep these in a manageable order.

If this care is not taken early in the preparation, the actual working with the slate either in marking and cutting or in putting the slates on the roof, will become very difficult.

'''Template – for marking and cutting\dressing.'''

Once the slates are selected and graded, a template is required in order to allow the marking and then the cutting or dressing of each and every slate. In the example roof there were over 4000 slates and each one requires two cuts to form a tapered shape – see image.[[File:Slate marking template 1.JPG|RTENOTITLE]]

Note : Not all slates should be cut or dressed at once. Mark and cut eaves course initially and fix these on the roof – this allows for any slight tweaking of the template or cutting technique.

For example, on the roof referred to earlier, with around 100 slates to each course, if the marking and cutting is just 0.5mm out an error can creep in very easily - 100 x 0.5mm = 50mm.

Take care to understand the setting out and cutting as you go. One word of warning – take time and do not get ahead of yourself.

Using a long piece of wood, plywood or two pieces of sarking board fixed together, make a working template. This template will form a shape which will be one part of the overall sloping \ curved roof – imagine an apple pie cut into numerous slices, each one the same size – it is similar to the conical roof, each slice (or the template) added together will make up the entire roof. see image [[File:Slate marking template 2.JPG]]The template dimension at its widest end will be the size calculated earlier by dividing the circumference of the roof (at eaves level + the drip or overhang remember) by the number of slates. The other end of the template will be a point. The length of the template will be the same as the length from eaves to apex on the actual slope of the roof (plus overhang into gutter).

Next the slate cover and gauge must be calculated – this does depend on the geographic location of the building on which the roof will be placed and also the roof pitch and type of slate. It is important to have these dimensions calculated and set out properly.

'''Slate Marking and cutting\dressing.'''

Each course is then marked onto the template. It is suggested that the template is supported on a bench or similar at around thigh height. Place one slate at a time on the template, face up and with the bottom of the slate aligned with the template course line and slate held centrally, mark or score the underside of the slate with a nail or pointed marker.

One tip – if marking and cutting 4000 + slates, it is worth taking that extra time to set the template properly and to also consider making a simple marking tool as holding on to a nail for 8000 score lines is painful.

Using the template, mark out a few of the eaves course – say 6 slates. Cut these first and try them on the roof to see how they sit next each other – check the angle by fixing a piece of thin gauge wire to the apex of the roof on a nail or bolt with a washer allowing the wire to be taken down to the eaves and all the way round the roof. The wire will allow the angle of cut to be checked – it should be close if the geometry calculations were done correctly and the roof structure is true.

Make any slight adjustments and continue marking, cutting and fixing the entire eaves course.

Cutting slates – depending on the slate thickness and how skilled one is with the slate knife, the lower courses may be difficult to cut and keeping to a straight line will be tasking. A heavier mash hammer can be used for these thicker slates, then revert to the slate knife as the slates become thinner – see video on you tube.

Next mark and cut\dress the next course and fix these to the roof, all the time checking the angle and ensuring the course is fixed true by checking with the wire - add a piece of insulating tape or similar to the wire to indicate the bottom of the slate in each course. Also use the wire to mark the position of the next row of slates – see photo. This makes nailing the slates onto the roof quicker if you have an entire course marked out in advance.

'''Nailing Slates.'''

The first few courses can be double nailed just as with any other roof, but as the slates get narrower toward the head of the slate higher up the roof , the slates need to be top nailed in order to provide cover.

The slates will also sit neater and tighter, if the top shoulders are cut off and the slates have been properly graded (Thicks, Middles, Thins) – see photo for shoulder cut.

'''Summary.'''

That is the basics and although it is extremely hard work and a very slow overall process the finished roof should be a work of art.

Any questions – please post on any of my pages and I will endeavour to respond. Just remember I am not a slater to trade, but a keen, hands on, Chartered Architectural Technologist.

File:Slate marking template 2.JPG

2013-03-11T22:18:25Z

Roundhouse Architecture: Image showing tapered template used for marking each course of slates

Image showing tapered template used for marking each course of slates

Conical roof slating

2013-03-11T22:16:58Z

Roundhouse Architecture: Created page with " This article is currently under development '''Traditional Skills - Slating a Conical or Turret Roof.''' As with any traditional skill or discipline, taking care and time to p..."

This article is currently under development

'''Traditional Skills - Slating a Conical or Turret Roof.'''

As with any traditional skill or discipline, taking care and time to prepare properly is essential and slating a conical shaped roof or turret using second hand Welsh slates is no different.

'''Roof geometry calculation.'''

It is important to consider the geometry of the surface to be slated which will be a sloping and curved surface or plane. Any natural slate is flat and the sizes available in second hand or new Welsh slate or any other slate will vary. Therefore consideration has to be given as to how a flat surfaced material will fit or sit on a curved plane.

In this article, as a recently constructed example, the roof referred to has a diameter at eaves\gutter level of 8500mm and a roof pitch of 40 degrees. The dimension from eaves to apex on the sloping line of the roof can be calculated by simple geometry. This dimension is important in the setting out and template making procedure.

Next the circumference of the roof is calculated, again using standard geometry. Note – Allowance must be made for any overhang into the gutter at eaves level, in this calculation.

'''Slate selection and grading.'''

The size or width of slate available for the eaves course is checked and it is best to use as wide a slate as possible as the slate widths will diminish in size towards the apex. Also important to ensure the largest size slate chosen will lie properly on the roof round the eaves course. The smaller the roof diameter the smaller a slate width may be required.

Once the size of slate for the eaves or starter course is decided the number of slates required to go round the circumference is calculated. This may not work out to an exact number of slates or slate width, therefore choosing the next round number up the circumference is then divided by the total number of slates. This is important to ensure each slate on each course all the way from eaves to apex, are the same width at the bottom of the slate on each individual course.

For example, all slates on the eaves course should have the same base dimension, just as the slates on any other course going up the roof will all have the same base dimension for that course, and so on.

Before any work is carried out on slate marking or cutting, an approximate calculation of the total number of slates for the entire roof is required.

There are several reasons for this – If the finished roof is required to have a graded appearance ie with thicker slates at the eaves gradually getting thinner towards the apex, all the slates have to be graded into say ‘thicks’, ‘middles’ and ‘thins’ – there may also be other thickness’s in between. By looking at the thickness of the slate and feeling the weight, the grading process becomes easier.

Add to this, the size selection as wider slates will be used on the first few courses and then to save cutting or wasting slates, narrower sized slates can be used higher up the roof.

Grading and sizing the slates is a time consuming job and also requires space to set out the various racks of slates to keep these in a manageable order.

If this care is not taken early in the preparation, the actual working with the slate either in marking and cutting or in putting the slates on the roof, will become very difficult.

'''Template – for marking and cutting\dressing.'''

Once the slates are selected and graded, a template is required in order to allow the marking and then the cutting or dressing of each and every slate. In the example roof there were over 4000 slates and each one requires two cuts to form a tapered shape – see photo.[[File:Slate marking template 1.JPG]]

Note : Not all slates should be cut or dressed at once. Mark and cut eaves course initially and fix these on the roof – this allows for any slight tweaking of the template or cutting technique.

For example, on the roof referred to earlier, with around 100 slates to each course, if the marking and cutting is just 0.5mm out an error can creep in very easily - 100 x 0.5mm = 50mm.

Take care to understand the setting out and cutting as you go. One word of warning – take time and do not get ahead of yourself.

Using a long piece of wood, plywood or two pieces of sarking board fixed together, make a working template. This template will form a shape which will be one part of the overall sloping \ curved roof – imagine an apple pie cut into numerous slices, each one the same size – it is similar to the conical roof, each slice (or the template) added together will make up the entire roof.

The template dimension at its widest end will be the size calculated earlier by dividing the circumference of the roof (at eaves level + the drip or overhang remember) by the number of slates. The other end of the template will be a point. The length of the template will be the same as the length from eaves to apex on the actual slope of the roof (plus overhang into gutter).

Next the slate cover and gauge must be calculated – this does depend on the geographic location of the building on which the roof will be placed and also the roof pitch and type of slate. It is important to have these dimensions calculated and set out properly.

'''Slate Marking and cutting\dressing.'''

Each course is then marked onto the template. It is suggested that the template is supported on a bench or similar at around thigh height. Place one slate at a time on the template, face up and with the bottom of the slate aligned with the template course line and slate held centrally, mark or score the underside of the slate with a nail or pointed marker.

One tip – if marking and cutting 4000 + slates, it is worth taking that extra time to set the template properly and to also consider making a simple marking tool as holding on to a nail for 8000 score lines is painful.

Using the template, mark out a few of the eaves course – say 6 slates. Cut these first and try them on the roof to see how they sit next each other – check the angle by fixing a piece of thin gauge wire to the apex of the roof on a nail or bolt with a washer allowing the wire to be taken down to the eaves and all the way round the roof. The wire will allow the angle of cut to be checked – it should be close if the geometry calculations were done correctly and the roof structure is true.

Make any slight adjustments and continue marking, cutting and fixing the entire eaves course.

Cutting slates – depending on the slate thickness and how skilled one is with the slate knife, the lower courses may be difficult to cut and keeping to a straight line will be tasking. A heavier mash hammer can be used for these thicker slates, then revert to the slate knife as the slates become thinner – see video on you tube.

Next mark and cut\dress the next course and fix these to the roof, all the time checking the angle and ensuring the course is fixed true by checking with the wire - add a piece of insulating tape or similar to the wire to indicate the bottom of the slate in each course. Also use the wire to mark the position of the next row of slates – see photo. This makes nailing the slates onto the roof quicker if you have an entire course marked out in advance.

'''Nailing Slates.'''

The first few courses can be double nailed just as with any other roof, but as the slates get narrower toward the head of the slate higher up the roof , the slates need to be top nailed in order to provide cover.

The slates will also sit neater and tighter, if the top shoulders are cut off and the slates have been properly graded (Thicks, Middles, Thins) – see photo for shoulder cut.

'''Summary.'''

That is the basics and although it is extremely hard work and a very slow overall process the finished roof should be a work of art.

Any questions – please post on any of my pages and I will endeavour to respond. Just remember I am not a slater to trade, but a keen, hands on, Chartered Architectural Technologist.

File:Slate marking template 1.JPG

2013-03-11T21:00:00Z

Roundhouse Architecture: Slate marking template showing second course slate already cut

Slate marking template showing second course slate already cut

File:Slate marking tamplate 1.JPG

2013-03-11T20:58:29Z

Roundhouse Architecture: Slate marking template showing second course slate already cut

Slate marking template showing second course slate already cut

User:Roundhouse Architecture

2013-03-08T21:37:31Z

Roundhouse Architecture:

I am a Chartered Architectural Technologist and director of Roundhouse Architecture Ltd.

I wish to share my experience in the field of architecture but also from a practical perspective having learned from my own trial and error and having gained valuable advice from others.

The first article I wish to write about and share is Conical Roof Slating and I hope this is of interest to readers.

You can view images which are regularly update on our website at [http://www.roundhousearchitecture.com http://www.roundhousearchitecture.com]

or our Facebook page at [http://www.facebook.com/pages/Roundhouse-Architecture-Ltd/149795131744042 http://www.facebook.com/pages/Roundhouse-Architecture-Ltd/149795131744042] 

I hope you enjoy the article as much as I have enjoyed the experience.

Norman McIntosh MCIAT

User:Roundhouse Architecture

2013-03-08T21:34:59Z

Roundhouse Architecture: Created page with " I am a Chartered Architectural Technologist and director of Roundhouse Architecture Ltd. I wish to share my experience in the field of architecture but also from a practical pe..."