Landscape cost estimating specialist Colm Kenny throws light on effective pricing for waste materials on landscape projects

Waste has a cost. The true price tag of waste is not just the bill from a waste contractor to remove a skip from the site, but a combination of expenses including material and labour. Contractors often underestimate the real cost of waste on a project as this is not an explicit one. By their very nature, the works carried out by landscape contractors generate large volumes of waste, both for construction projects and maintenance operations. The cost of discarded materials disposal is becoming more expensive as more stringent controls and tax levies are being placed on dwindling landfill sites.
To remain competitive the landscape industry as a whole needs to seek ways of minimising waste. While the concept of waste management has been embraced by the wider construction industry, the landscape sector still lags behind when it comes to adapting to waste control techniques.

CONSTRUCTION PROJECTS

Bill of Quantities are important documents on construction projects as they state what quantity of material is required for each element of the project. However, apart from the disposal of surplus excavated material, they do not inform you what waste will be generated. Take a simple patio construction project as an example. Apart from the cost of disposal of excess materials, other added costs could include the price of surplus materials, additional delivery charges, and the labour required to first cut the paving slabs to the required size or shape. All these costs must be calculated in the contractor’s rates when building up a rate per square metre for the project. Experienced contractors will know that, depending on the design, they will often have to allow an additional 10-15% minimum to cover off-cuts, breakages, changes in levels or interfaces with other materials.

I recently completed a project as project manager for a firm of architects in which landscape design included a semi-circular patio at the entrance to a hotel, which was constructed from 600 x 600 x 50mm limestone paving flags. The Bill of Quantities had the correct finished size of the patio measured, which the contractor-priced. However, he failed to make any allowance for additional paving slabs to cut in order to form the required shape and at the end needed to purchase an additional 40% of materials at his own cost. Needless to say, he wasn’t too happy at the end of the project.

“Landscape designers have a massive role to play in terms of reducing waste within the industry”

Landscape designers have a massive role to play in terms of reducing waste within the industry. Design and the specifications can contribute significantly to the amount of waste generated during the construction of a project, particularly when uneconomical design solutions are selected or when unsuitable materials are specified. Careful consideration and specification of material sizes can have an impact on reducing waste. Going back to the paving example, the size of paved areas can be designed to accommodate as many as the specified paviors as possible while minimising cuts.

When tendering for a project, contractors must endeavour to estimate the cost of the waste that will be generated by each operation. Once that cost has been calculated, it often has the effect of getting contractors to focus on methods of reducing waste. Reducing the wastage of materials should result in more competitive tender rates and an increase in profit for contractors.

There are some simple ways in which contractors can reduce waste. For example, prior to placing orders for materials, ensure that the information used is up to date and accurate. From my experience, cost-cutting exercises by the client, architects and main contractors always seem to involve the landscape scheme, so therefore the scope of works could have changed since the tender stage. Do a crosscheck on the key materials by measuring the
quantities of materials required, and ensure that the drawings are available in digital format so that the information extracted is accurate and to scale. Lastly, carry out site measurements as quite often more accurate information can sometimes be produced if site measurements can be carried out. These are particularly useful when drawn information is limited.

MAINTENANCE PROJECTS

It’s a familiar sight during the maintenance season to see trailers of green waste on the move to the local green waste depot. This waste has a huge cost associated with it, both to the client and also to the contractor. It is also not an item that contractors can make a huge profit on as it is often hard to justify to clients the expense involved. They just see the maintenance works as the only cost and once the trailer is gone out the gate fully loaded it’s forgotten about.

Quantifying the volume of waste produced from maintenance works is a difficult procedure, especially when you are tendering for a project on a site you are unfamiliar with. It will be the case that the outgoing contractors will have the advantage of knowing what waste is generated as they will have a working knowledge of the site. However, a calculation is required, even if it is only to be used as an allowance to be put into your tender bid. Lack of specification of maintenance works can also lead to a difference in price and standards between competing contractors as it comes down to perception of the required standard, but that’s another day’s work.

“Calculate accurate fuel costs by using sites such as the AA route planner”

Most local authorities have a green waste depot where they accept green waste from contractors. However, contractors need to include in their rates not just the cost of entering into the landfill but also the transport cost associated with it. As it is a hidden cost, it can be overlooked by contractors when calculating their rates. With a number of websites, such as the AA route planner, capable of calculating fuel costs from point A to point B, it is important that this is calculated as accurately as possible and not contained in a contractor’s overheads and profit. While the cost of fuel has fallen in the last number of months, it won’t stay this low forever and so a provision for price fluctuation in the future should be allowed.

One way contractors can reduce the costs associated with generated waste on a regular maintenance contract is to an onsite compost facility if there is not one already. This doesn’t have to be anything complicated, a simple structure composing of railway sleepers and a surrounding screen will suffice. The benefits of having such a facility on site are three-fold to the contractor. Apart from the entrance fee, the transport and labour costs filling the trailer are eliminated. Also, time wasted on traveling to the depot is removed, allowing for increased productivity and a longer working time on site. The generated compost can then be used as mulch on the surrounding beds, further reducing your need to pay out money on such materials.

In order for a client to accept such a proposal, it may be necessary to offer them a discount on the works. However once this discount is within reason, it will be beneficial to you, and pay dividends in the long run.

THE FUTURE

By focusing on the way waste is generated and its associated costs, the participants in the process will be able to understand what their wastage is and then be able to take action to reduce it. This process needs to begin with the designers of landscape schemes and in turn, educate contractors to the cost benefits of reducing the volume of waste generated. ✽

COLM KENNYCOLM KENNY, B Ag. Sc. (Land. Hort), M.Sc. Quantity Surveying. Colm is a landscape estimating specialist. He provides cost and implementation advice to landscape industry professionals, technical advisors, contractors and facility management companies.
He can be contacted on 087 288 5016 or by email info@landscapeqs.ie

RELATED ARTICLESMORE FROM AUTHOR