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	Detailing Block Paving

Curves and Arcs   Mitred Edge Courses   Manhole Detailing   Rodding Eyes   Design Features

 

Detailing Block Paving
Detailing could be described as the 'finishing touches' to a good block or brick pavement. It refers to the way corners are set out, or how the paving is laid around manholes, gullies or other fixed features. Tidy detailing is usually the hallmark of a good block layer; it reveals a tradesman's sense of integrity and professional pride in the finished appearance of the work. Some projects have little or no detailing, but most have at least some features that should be detailed, even if it's only mitred corners to a soldier edging course.
Curve detail Curves are a common feature of most block paving. The small unit size lends itself perfectly to constructing curves, arcs and circles, which give a pavement a more organic look than does regular geometric shapes such as triangles and rectangles.
In practice, it's very simple to construct arcs of more than about 2 metres radius using full blocks. Mathematically, a 2.1 metre radius arc gives a maximum joint width of 10mm,although this figure will be 10-13mm on site, which is about the limit for a sand-filled joint. Any curve or arc of less than 2 metres will need extra work to deal with the wider-than-acceptable joints.	2 metre arc formed from full blocks
There are two solutions to the problem of these wide joints, to fill the joint with mortar or to cut the block to a taper shape. While both solutions are perfectly acceptable, the cutting option gives a more professional looking finish and requires a higher degree of skill.
0.9 metre arc with mortared joints	On fast arcs of radius 1 metre or less, the mortared joint option becomes impractical as the open joint width exceeds 30mm, and these bricks will have to be taper cut. Any joint wider then 30mm pointed in mortar looks shoddy and cheap and is usually a good indicator of a slap-dash approach to the job. From an engineering viewpoint, unless the mortar is strengthened with SBR or similar, it will more than likely crack away from the brickwork over time, and be prone to damage from sharp heels etc.
If a mortared joint is to be used, then the mortar should include a strenthening/bonding agent, such as SBR, and should be coloured with a quality concrete dye to complement the paving. A red mortar looks good with any of the red colourways, such as 'Brindle', and a black mortar looks best with charcoal or dark brown blocks. If using a black mortar, use a silver sand, as this requires less dye per kg to acheive a good black colour than does red or yellow building sand, which tend to turn dark brown rather than black. See Pointing Tips for a guide to mortar pointing joints
Taper cut joints not only look better than those pointed with mortar, they are less likely to cause problems. For radii between 0.6 and 2.0 metres, only one edge of the brick needs to be cut. Make sure that the same edge of each brick is cut, so that two cut edges are not butted together to form the joint, and the curve remains 'sweet'.	Curves formed with taper-cut blocks
Lengthways cuts on block pavers can be quite difficult unless the blades on the splitter are sharp. Clay pavers are exceedingly hard, and it's often quicker, easier and results in less wastage, to use a diamond-tipped bench saw to cut the taper blocks. See Cutting Block Paving for more details
500mm radius arc showing single edge tapers and double tapers	Curves and arcs with radii less than 0.6 metres need the block to be cut on both edges to create a good looking taper. If only one edge is cut, the length of the cut edge is slightly longer than the uncut edge of the adjacent block, and this leads to a jagged-looking appearance to the curve. By cutting both edges, and this is best done on a bench saw rather than a splitter, regardless of block type, the arc is kept 'sweet' and the blocks don't look 'skewed'.

Although trimming the edge of each block in a radial soldier course makes a neat, sweet curve, as on the left, alternating taper cuts with uncut blocks can also acheive a reasonable curve, (on right) but somehow, it just doesn't look quite as professional.

Mitred edge course detail Edge Courses, their functions, their construction and a gallery of some of the more popular choices, are considered in much greater depth on a separate page. Mitred corners occur where two lines of soldier edging meet at an angle. Quite often, they form a true 90° corner, as at the corner of a house or garage. Mitring is less visually effective with single width block edgings, except at non-orthogonal angles, but can be used if so wished. The series of sketches that follow illustrate some of the more common mitres found in block pavements.
Soldier edging showing mitres for different angles.
The bog-standard un-mitred vertex between two lines of soldier blocks at 90°. It's simple, it's straightforward, it involves no cutting and virtually no skill, but it's the most common vertex seen on driveways and other block pavements. While there's nothing wrong with it, technically speaking, it lacks class and indicates haste and simplicity were the driving force behind this installation, rather than a willingness of the block layer to show off their skills.

The Corner Mitre

In the photograph above, note the use of a narrow 'slip' to the left hand edge of the vertex. This is wrong - instead of using a 20mm wide slip, the cut block and the block to the left of it should have been replaced by two blocks cut down to 60mm width, as shown in this photograph of a properly mitred corner

A standard mitre

The corner mitre shown in the photo above only works with angles ranging from about 60° to 120°. For other angles, standard mitres are preferred. The transverse mitre shown on the right is neat and tidy, but breaks the alignment of a standard Soldier course by introducing a third angle and the consequent third block orientation, and relies on using a small, triangular cut block at the vertex of the mitre.

Transverse Mitre

Double stretcher edgings don't really need a mitre at 90° corners, but they are needed for non-orthogonal angles (angles not equal to 90°). If mitred angles have been used elsewhere within the edging course, mitring the 90° corners will keep the appearance uniform.	Double stretcher edging with and without mitre
Stretcher edging showing mitre for 45° angle.
See the Mitre Joints page for a much fuller discussion of the principles involved in creating mitred jopints for all types of paving.

Manhole detail Manholes are often unavoidable within a paved area, although the use of recessed tray covers can make them 'disappear' into the body of the paving. However, there are circumstances and situations that make the use of such a cover impossible or impractical, and there is no alternative other than to pave around the manhole cover, or other fixed feature. In most cases, the position of the manhole cover is fixed, and the paving must be made to fit around it. This can result in small 'darts' and other blocks abutting directly against the frame of the cover, and so to avoid this, the use of an edging course around the cover allows the paving to be cut-in to avoid these undesirable partial blocks.
Rectangular covers
Detailing around rectangular manhole covers
A double or single width edging can be used as shown in the diagram above. Note the use of a pair of trimmed blocks to complete the dging course to each side - this has been omitted in the botttom right corner to show how a thin 'slip' block looks awkward. They are also prone to snapping as the longitudinal length is that much greater then the width. The corners can be mitred as discussed above, and the use of half blocks within the body of the paving eliminates the 'darts', as shown on the cutting-in page.
Circular covers
Circular manhole covers, usually 450mm diameter domestic inspection chambers, will need the blocks to be cut to a taper to form an edging course around the circumference.
Detailing around circular manhole cover	Tapering both longitudinal edges by cutting on a bench-saw, results in a more balanced looking and professional surround, as shown on the left. A single edge taper cut looks 'skewed' when viewed in plan, as shown on the right, although this is less noticeable when viewed from normal eye level.	Alternative detailing around circular manhole cover
Single width edgings around a circular cover also look better when taper cut to both edges, but can be made to look very good with only one edge tapered, provided that the cut block length isn't too long. In the examples below, the centre drawing has an edging course formed from blocks measuring 125mm along the longest, external edge. The drawing on the right has used blocks with a maximum edge length of 175mm, and the result is jagged and untidy.
Single brick taper cut to both edges	Single brick taper cut to one edge only	Taper cut to one edge but units too long

In the photograph opposite, the taper cut principle outlined above has been applied to the edge blocks laid surrounding a 300mm diameter support stanchion. This has not been done purely to create an aesthetically-pleasing finish to the stanchion, but it actually makes cutting-in the blocks used for the body of the paving so much easier, as the size and angle of cut can be determined more accurately than would be the case if cuts were required directly against the stanchion itself. See the Edge Courses page for further discussion on the use of edge courses to simplify cutting-in tasks.

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Recess Tray Covers The fitting of Recess Tray Covers is dealt with on a separate page
Recess Tray Cover	Unlike other manholes covers, recess tray covers are not surrounded by an edge course, but the pattern of the paving is maintained, to make the cover less noticeable.	Recess Tray Cover

 

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Around Rodding Eyes Rodding Eyes (RE) are a bit of a nuisance when it comes to block pavements. They can't be disregarded, as they are essential access points to the drainage system beneath, and they are a royal pain in the arse to pave around, but they are so small that they hardly warrant the use of a recess tray. Specialist suppliers can offer smaller trays, such as a 300x300mm unit, that would be a suitable replacement for the standard aluminium Rodding Eye cover (shown opposite), but most Builders' Merchants do not have them in stock, and it can be a 5 day wait to have one delivered to site.

The awkward shape of both the RE cover and the connecting pipework makes for difficult construction of a block pavement around the structure. Unlike most other 'ironwork' (the trade name for gratings, manhole covers and the like), a RE cover doesn't have vertical sides, but has one edge that undercuts itself while the opposite side splays outwards. If the RE cover is to be retained within the block pavement, then the following method has been found to be a successful way of dealing with them and presenting, on completion, a respectable looking finish.

The RE cover and connecting pipework should be surrounded by mass concrete, as shown in the cross-section drawing, so that the structure is supported and a bed provided for an edge block surround to the cover. A C20 or equivalent concrete (roughly 1:2:4 or see Concrete Mixes page) is adequate for most driveway applications.

The edge blocks will need to be cut to shape, and this is best done with a Power Saw. By using a relatively narrow edge course, such as the 100mm band shown in this example, the number of tightly angled cuts required is kept to a minimum, and the presence of the RE cover is not overly promoted. Note that, on the splayed side of the RE cover, the edge blocks will need to be undercut to sit atop the cover. The 3 or 4 blocks in this spot may be better bedded onto a shallow bed of finer concrete or a Class II mortar overlying the mass concrete, so as to ensure full support.

Once the edge blocks are in place, the surplus concrete/mortar can be removed, the joints sanded, and the paving work can continue as per normal. Once the remainder of the paving is in place, there should be no problem traversing the RE cover and the edge block detail with the plate compactor.

Feature details Block paving is without a doubt one of the most attractive looking paving surfaces that can be used, but in large swathes, it can lose itself, become over-bearing and bland, almost. We find that large areas of block paving can be visually enhanced by inserting patterns and features within the paving.
The clearest example of this is the use of diamonds within 45° herringbone paving. These diamonds are very simple to insert and can give a drive entrance an impressive look, or can be used to break up large areas into 'visually manageable' areas, to draw the eye along certain lines of sight and away from others, and give the impression that this is a section of paving that someone has put some thought into.	Diamond Feature by Carl Beardsmore
Simple single diamond/square feature	Diamond or diaper pattern in stretcherbond blockwork

Click on images for full size diagrams Diamond features on 3m wide pavement	It is possible to insert diamonds into any paving pattern, although patterns not set out at 45°, such as a stretcher bond or basketweave, will require a lot of angled cutting to accomodate the diamond. In a 45° pattern, only half blocks are required, which makes them the simplest of all features to insert. With diamonds, we find that it is easiest to lay the body of paving in the chosen block, and then place the diamond, in a contrasting colour block, over the top of the paving. View from various angles or an upper-floor window to get the size and position of the feature exactly right before fixing it into the paving by removing the underlying blocks and replacing them with the blocks that will form the diamond. Trying to build a diamond, or any other isolated pattern feature into a pavement as it is laid can often result in it being off-centre or out of scale.
And diamonds are not the only features that can be built into a block pavement; circles are popular too, so much so that most of the big manufacturers now supply ready-made circle packs in various forms of paving. Unlike the diamonds above, it's easier to set out and lay the circle on the prepared bed and then complete the body of the paving around the circumference.		Circle Feature
Another popular item is to build-in the initials of a company or the house number, although quite why anyone should want a 1.5 metre high number 32 outside their home is beyond me, but, as they say, whoever pays the piper calls the tune. These need to be scaled in accordance with the size of the project, and are best prepared after the body of the paving has been laid, positioned on top of the pavement and scribed around with chalk. Take up the blocks bearing chalk marks, insert the letters, numerals or other figures, and cut in the body of the paving to suit.
There's no limit to what figures, symbols, or just about any other design can be built into a pavement. The more complex designs ought to be planned out on paper or a CAD program before starting out, and it must be borne in mind that what looks like a fantastic decorative design in plan view, can look a mess when viewed from ground level.		Horse Feature at Tetley's Brewery in Leeds, constructed using Marshalls Pavers
Close-up of feature	A contrast can be made by using not only different coloured blocks, but by creating the design from a different type of paver. The picture opposite shows a close-up detail from the horse design above, and uses Marshalls red Nori Clay Cobbles to form the design within the body of the Tegula paving. The small size of the Nori Cobbles make them ideal for marking out arcs, curves or other patterns.