How can you account for unexpected costs in landscape architecture projects?

To account for unexpected costs in landscape architecture projects, thorough initial planning and ongoing project management are essential. Incorporating a contingency fund within the project budget, typically ranging from 5% to 10% of the total project cost, helps cushion unforeseen expenses such as site complications, material price fluctuations, or design revisions. Regularly reviewing and updating project budgets and schedules also ensures that any deviations from the initial plan are promptly addressed, allowing for informed decision-making and effective resource allocation.

In my experience , identification of zones at the earliest stage of the project is critical, you may not have much at your disposal, but knowing where to allow for hard landscaping and where to allow for soft landscaping over a large area can make a huge difference. Also having some understanding of the indigenous plant species and the supply and installation cost relating thereto.

Unexpected costs in Landscape Architecture are usually related to the methodology approached by the teams and their location. If there would be a list of unexpected costs, most probably you would find they are similar within design teams, construction teams, location(work culture and legal environment) and clients. A clear and healthy relationship with this four areas is crucial to understand scope and therefore to reduce unforeseen expenses.

As unexpected costs arise throughout the total design journey: scope creep, construction costs, contractor availability, supply chain... account for these 'known-unknown' potential landscape over-runs like any other design element: lock concept integrity, or, 'design intent' across all disciplines relating to key spaces across scales as a whole, regardless of wether internal or external spaces. That way when the 'essential / nice to have / delete' conversations arise, some landscape spaces are protected, others can be seriously down specced - like other disciplines. Always bake the good stuff in.

Tener claras las etapas del proyecto, que tiene que ver con el nivel de definición, desde el proyecto conceptual hasta el ejecutivo y la supervisión en obra. Sin dejar de lado las reuniones con contratistas y especialistas que intervienen en el proyecto.

In my experience the best way to start cost estimation is by building a thorough well defined CBS (Cost Breakdown Structure). Building a thorough CBS diminishes the risk of scope gaps.

During the cost estimating phases I recommend estimators to generate the initial risk register ideas. Update risks as the project estimate design levels progress. Estimators should deliver good project risk items. The other stakeholders can focus on systemic risks.

Here's the deal: cost estimation isn't just about crunching numbers. It's about understanding the intricacies of your design, the resources at your disposal, and the ever-changing terrain of the project. That's why there's no one-size-fits-all approach. Whether you opt for parametric, analogical, bottom-up, or top-down methods, it's crucial to tailor your strategy to fit the unique contours of your project.

I recommend the cost estimators develop least likely, estimated cost and most likely costs for all project risks. Many times risks values are placed until dollar threshold value buckets. IMO the EMV of the risk register can be very inaccurate to reality.

As a seasoned landscape architect, I've learned that controlling the budget is like nurturing a thriving garden – it requires constant attention, a keen eye for detail, and a touch of finesse. So, when it comes to managing project finances, here's the dirt on how to keep things blooming smoothly. First things first: stay grounded. Embrace tools like cost variance analysis, earned value analysis, and cash flow forecasts to keep tabs on where your money is going. These techniques aren't just fancy jargon – they're your compass in the financial wilderness, helping you steer clear of any budgetary weeds.

Start with analysing current project financial status, investigate upsides and downsides of different disciplines/trades. If budget is available present to the client for approval (budget control), if not refer to change management.

Once the cost estimate and the risk register are completed in early design phase. I recommend running a Monte Carlo simulation (MCS) on cost estimate and high risk register items only. Delete contingency from the estimate before modeling. Modeling all the risks just adds unneeded noise to the simulation. Only model high risk elements in the cost estimate as well. Once modeled the MCS should give a P50 value where the project is a 50/50 coin flip on being successful. If your organization has a higher risk threshold use a higher P-value. The original estimate less the P-50 should be considered project contingency. Any dollars above P-50 are considered management reserve.

-Site conditions: Unforeseen issues like poor soil quality, underground utilities, or environmental restrictions may require additional work or materials. -Weather Delays: Adverse weather conditions can disrupt construction schedules, leading to increased labor costs or the need for protective measures. -Regulatory Changes. -Material Price Fluctuations. -Scope Creep: Client requests for design modifications or enhancements beyond the original scope can add expenses for design revisions, materials, or labor. -Subcontractor Issues: Delays or errors from subcontractors, such as irrigation specialists or lighting contractors, can result in additional costs to rectify the issues. -Unforseen design changes. -Site Access Challenges.

Set a Contingency Sum of 5-10% of the project sum to cater for anything unexpected, unaccounted and important for the continuity and progress of the project.

The best method of management within our projects has been working on a time and materials basis. I have never overcharged a client and I can offer commentary and solutions in real time to problems that the designers sometimes never consider or relate to the client. Today in fact we found a lockset that was 1/10th the cost of an architects choice. These types of small value engineered changes are never realized by the client in a fixed cost scenario. T&M prevents the client from paying too much and the contractor from missing something in the scope. Most contractors spend a significant amount of time guessing. This is the least desirable and riskiest way to engage in our business.

The best method of management within our projects has been working on a time and materials basis. I have never overcharged a client and I can offer commentary and solutions in real time to problems that the designers sometimes never consider or relate to the client. Today in fact we found a lockset that was 1/10th the cost of an architects choice. These types of small value engineered changes are never realized by the client in a fixed cost scenario. T&M prevents the client from paying too much and the contractor from missing something in the scope. Most contractors spend a significant amount of time guessing. This is the least desirable and riskiest way to engage in our business.