14 Jun 2015 • What is Site Preparation?

Perhaps the most common question we receive regarding our land clearing services is some variation of “How do I prepare my land for building?” which translated into construction lingo means “what is site preparation?”. This is a serous question worthy of a thoughtful and thorough explanation, especially in light of the lack of information available on the subject. The mere fact that site mitigation ( i.e. fixing failures) is an enormous industry in itself speaks volumes about the ignorance and neglect surrounding the matter. It has been our experience that if clients adopted some form of the formal strategy outlined below the entire construction process would go much more smoothly. Scheduling delays would be avoided. Potential negative environmental impacts would be addressed from the start. The final product would be more durable, attractive and livable in every regard. As it stands, billions of dollars in errors, waste, lost time and legal entanglements plague the construction industry, much of this the result of poor site preparation and inadequate planning.

Site Preparation Requires a Good Leader

Site prep is best overseen and organized by a single person or entity. This person is basically a team leader who’s principle job is to foster the coordination and communication necessary to ensure cooperation between all individuals involved. This could be an architect, builder, professional project manager or even the homeowner. The only requisite is that they adhere to the iterative process. A dedicated novice or project manager can potentially do as good a job as a professional in one of the relevant fields if they have good communication skills, are detail-oriented and willing to learn some basic technical requirements. Often architects, engineers, builders, homeowners etc. think in a fashion reminiscent of the fabled men who, blindfolded, described the parts of an elephant in entirely different ways. While each profession must bring valuable insight to the project, each must serve the larger site preparation process as a whole. Sadly, because organizational authority is often lacking, direct cooperation between relevant professional fields is insufficient for a successful outcome.

Why Your Builder Should Not Be Your Only Choice to Oversee Your Site Prep

At this point some of you may be asking “Isn’t site prep the responsibility of the builder?” The answer is both yes and no. Builders are often accountable for its success or failure but this can be more of a problem than a solution. Builders are usually “house-centric” and generally much more comfortable with the actual home construction than the somewhat esoteric science of site prep. On numerous occasions we have seen expressions of great relief on the part of builders after suggesting that we work directly with the designer, engineer and client on the site prep. Often builders simply inherit a process that began prior to their arrival and without their input. The grading contractor usually ends up in the same boat. They may have decades of earthwork experience but they are there on a “low price bid” to do a given number of tasks with little creative input. All end up being subservient to a hurried momentum and preset budget even when they appear to have autonomy. This results in the omission of essential planning steps and ultimately mistakes. Who ends up in charge? The budget. The bottom line overwhelms real value and the process becomes, as my seven year old says, “mangalated”.

So What Can Be Done To Ensure Your Site Prep Is Successful?

You have your land or lot and now you want to begin the building process. The first step in site preparation is site assessment. Site assessment should include all relevant aspects of your land and not merely your building footprint. Our company uses basic digital mapping techniques to create multi-layered site maps, often of entire properties. This allows us to look at your land as a whole. Map layers include topographical profiles, high resolution aerial photography, soils identification, timber assessments, riparian and wetland demarcations, access, previous land use, adjacent property lines and more. Mapping is cheap and provides a starting point for all parties involved. It creates good general orientation on the ground. It is not, however, a substitute for good “on site” investigation. There is no substitute for familiarity. It is necessary to be able to see and walk your site. If it is too overgrown you should underbrush it. This will assist everyone involved and, where forestry mulching is appropriate, provides basic erosion control and soil protection from the outset.

Know You Planning Requirements

Another component of thorough site assessment is gaining an understanding of relevant planning and zoning requirements. Development guidelines sometimes extend all the way from national requisites, mandated by the Clean Water Act, down to individual subdivision covenants governing minimum square footage and specific design elements. In addition, municipalities have basic rules regarding setbacks (proximity of structures to adjacent property lines, public roads, utilities etc). Some also have steep slope ordinances requiring sites within certain parameters be subject to additional design requirements such as stability analysis, maximum allowable de-vegetation, building height etc. Remember to also check with your local utilities. Most have very specific guidelines regarding services for new homes. All these requirements must be factored into the design process from the outset. To do otherwise, as we have have seen on many occasions, always contributes to confusion, delays and cost over-runs.

Time To Develop Site Documents

Assuming your future building area is now accessible the formal process of creating site prep documents should begin. It is time to develop a higher quality survey or DEM (Digital Elevation Model) of all impacted areas. These survey maps generally work off two foot contour lines so that engineers, architects and grading contractors can make accurate calculations and work swiftly. DEM’s are created by surveyors working for you or your selected builder, architect or engineer. These more refined maps capitalize on previous mapping efforts but focus on the building area, even down to individual trees, springs, rock outcroppings and specific soil analysis, the latter of which is absolutely essential.

Inadequate soil analysis is more responsible for site failure in the mountains than any other single factor. Soil related issues, especially erosion, wall, foundation and slope failures, account for a huge percentage of our mitigation work. Some soil complexes, such as colluvials and micatious soils, are simply unsuitable for construction. We recommend clients employ the services of a reputable geotechnical engineer to “at least” examine their site prior to the creation of construction documents. Geotechnical services, from basic site walks to complete borings and analysis, are typically not expensive and can ensure your site and building design are appropriate from the start. You don’t want to be nearing the completion of your home (and budget) only to find out you need a $ 50,000 retaining wall or foundation fix.

Once your contour survey and geotechnical investigation are complete the process of designing the home in a way that integrates it into the land can begin. You, your designer, engineer, grading contractor and builder, and later various subcontractors such as electrical, gas, HVAC and plumbing, can work off the same page. Often we are presented with house plans purchased from builders’ portfolios or internet sites. The idea is simple, to eliminate design costs and speed up the process. This seldom works in reality. House plans floating on a white page must ultimately be grounded firmly on Mother Earth. We are called upon to evaluate and correct tens of thousands of dollars worth of mistakes associated with this foolish shortcut annually. Nevertheless, we encounter this failed notion on an almost daily basis. At the very least, the lack of complete and/or unintegrated site documents creates big cost overruns and second rate solutions.

What Kind Of Site Documents Do I Need And How Do I Get Them?

Hire a local architect to design your home or modify your chosen plans. The money you spend on a skilled local architect or designer will come back to you in many ways once actual construction has begun. A good architect will be familiar local planning and zoning guidelines and will also connect you with local resources, including respected builders and material suppliers. The process of working with an architect informs more than just the look and feel of the home. Crucial issues such as positioning, (especially for solar installation and view sheds), access, structural retention (walls), drainage, rough and finish grading, revegetation, landscaping and more are addressed. You are paying your designer to leverage their skills and experience on behalf of your future living experience and budget. Better yet, bring pictures, sketches, ideas etc. to the table. Learn as much as you can. Ask the stupid questions. Listen. Demand deadlines be met. And, above all, keep the process moving. A good architect will be a tremendous asset and resource for you and your builder.

After all, you are working towards a set of finished renditions or “elevations” that portray all aspects of your home on paper as it should look on your land. A complete set of construction elevations provides valuable calculations and visualization for everyone involved in the construction process. They allow for superior task consolidation and better communication. As an example, accurate grading elevations or grading plans, such as those created by architects and civil engineers, provide static benchmarks, show graders where and how much soil to excavate and/or fill, where to install erosion control, how to construct necessary access, what finished slopes and walls are desired, where septic, water, gas, electrical and IT lines should be placed and much more. If mistakes exist they are likely to be caught on the prints themselves prior to breaking ground.

It’s Time to Build a Team Mentality

Now that conversation is underway it is time to bring the grading contractor directly into the mix. Resist the advice to simply allow the builder to use his “regular guys’. or to just throw the plans out into the world for the cheapest bid. An experienced grader usually has a better feel for the tasks associated with site prep than anyone else, in particular native soils, hydrology, specific materials and overall costs. Find a reliable excavation contractor with an impressive portfolio and solid recommendations. Have him or her walk through the excavation process with you and your builder, and even take you to an ongoing project. A well run site has a sense of industry and precision far different from a poorly run one. For the most the prevailing paradigm dictates that grading contractors works as subcontractors under builders. This is often a poor arrangement as most builders don’t have professional grading experience. In many cases a good grader can make major modifications to your plans: correcting oversights, cutting costs and improving the overall outcome. In addition, it is often wise to include a local arborist. Where sites are heavily vegetated it will be necessary to determine which trees must be removed and which must be protected. Both tasks represent costs which must be known from the outset.

Don’t Underestimate the Importance of Landscaping

Now the team is growing the discussion is evolving and you are beginning to feel more comfortable with the process. This expanded level of planning obviously requires good communication. Any party that fails in the planning phase or does not agree to multiple, on-site planning sessions should not be retained for the construction phase. In many cases the inclusion of a landscape architect provides the finishing touch. We generally believe at least 10% of a total building budget should be retained for landscaping. By landscaping we are referring to much more than flowers, bushes and lighting. We are speaking of the way in which your home fits its specific landform and ecological niche as well as important structural elements such as soil management, revegetation, drainage and structural retention. We are referring to your outdoor living, privacy and interface with other living beings. A skilled landscape architect works hand in hand with you, your home designer, engineer and builder, employing the same maps and data to create the finished look of the home. Large architectural firms employ their own landscape designers and do this “in house,” as part of your design process. We recommend you have direct involvement with your landscape designer.

Money Spent on Planning is Money Saved During Construction

By now you are probably wondering how much time and money all this planning and convening costs. The simple answer is unequivocal – less than making a mistake. Planning and site documentation are not merely permitting requisites. Thoughtful planning and good site documentation help ensure cost savings as well as a speedy and successful home construction. In fact, planning as a team routinely speeds the process up. We suggest participants schedule conference calls to discuss their project. Conference calls are an inexpensive and effective way to bring all thoughts and opinions to bear. We found that folks don’t want to show up unprepared or seem overbearing or egotistical during a call. Conference calls diminish distractions and build cooperation while moving the project further down the road.

Good planning budgets are investments that pay back with high interest

A decade ago, when our young company was still involved in actual home construction, we spent a winter in San Francisco remodeling an older home. The blue prints were so detailed and well thought out we never once spoke to the architect. Every inspection passed and the house was completed ahead of schedule and under budget. This degree of exactitude is worth striving for. It pays you back in multiple ways. Your construction moves much more swiftly with fewer uncertainties. Mistakes and oversights are caught in the planning phase. Subcontractors are able to bid or estimate within tighter margins. Ultimately your house is both more livable and more valuable. This is to say nothing of financial institutions, which tend to lend more generously on projects with clearer objectives.

A Few Other Ways To Insure Success

Finally, there are some basic recommendations that can be followed to assist successful site preparation from the outset. For starters don’t build on land that is too steep, has poor access or volatile soils. Many buyers fall for view lots with poor access, a major pitfall. Create a house design that compliments your land. Don’t attempt to bend Mother Nature to your will. As a rule, the higher the site prep budget, the farther you have strayed from your site’s native design constraints. When deciding on a designer do your homework. Talk with previous clients and visit their homes if possible. Shrink your footprint by at least 20 percent. Americans build the largest houses in the world. Cutting your footprint down saves big bucks from the ground up and allows more money for fine finish work and landscaping. Finally, make certain your builder has a skilled systems designer who deeply understands modern heating, cooling and insulation techniques. Good mechanical design contributes mightily to livability, value and long term cost savings.

Site Prep Basics In Conclusion

There are really only a few basic rules that must be followed to guarantee successful site preparation:

Make your land accessible and conduct a thorough site assessment. Map your property to gain a better general perspective. Be especially diligent regarding soil analysis. Hire a geotechnical engineer to evaluate your site, especially if it is steep, wet or rocky.

Understand all applicable planning and zoning requirements and ordinances. This includes those prescribed by your local utilities. Ignorance will not be an excuse once boots and tracks hit the ground.

Hire a local architect or designer and build a team that includes all relevant professionals (grading contractor, civil engineer, arborist, landscape designer etc.) Keep the process moving! Use conference calls for this purpose. Site preparation is an iterative process with lots of opportunity for “balls to be dropped.” Remember, a team without a leader is no team at all.

Work towards complete visualization of your home as it will appear when finished. Create the documentation that allows this, i.e. DEMs, complete construction elevations, grading plans and landscape drawings.

Educate yourself regarding sustainable design and basic construction methods. Learn a bit about technical matters such as: foundation design, structural retention, HVAC and utility hook-ups, alternative power, driveway placement, septic installation etc.

Most importantly, Listen! Ask the stupid Questions. Your understanding and direct involvement during site preparation phases lay the foundation for successful home construction…literally! They also contribute to enormous cost savings and a better home.