Historic Structures Report
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This opinion of probable cost has been prepared to reflect the anticipated cost of rehabilitation, restoration, preservation and stabilization of various historic structures, located at Cabrillo National Monument, San Diego, California.

This document is based on the measurement and pricing of quantities wherever information is provided and/or reasonable assumptions for other works not covered in the drawings or specifications, as stated within this document. Unit rates have been obtained from historical records and/or discussion with contractors. The unit rates are a composite of labor, material and equipment and reflect current bid costs in the area. All unit rates relevant to subcontractor works include the subcontractors' overheads and profit unless otherwise stated.

The following documentation was used in preparation of this opinion:

  • Historic Structures Report, prepared by Carey & Co, draft dated April 30, 1999.

  • Revised Treatment Recommendations, dated October 5, 1999

  • Xeroxes of photographs and maps, prepared by Carey & Co, dated August 4, 1999.

  • Conversations and meetings with the architect.


The following items are excluded:

  • Land costs
  • Consultant fees and expenses
  • Fees for testing construction materials
  • Plan check, inspection, testing and utility connection fees
  • Permits
  • Moveable furniture and furnishings
  • Indoor plants and planters
  • Equipment other than stated
  • Legal and financing costs
  • Fire and all risk insurance
  • Demolition other than stated
  • Off-site utilities
  • Escalation beyond Midpoint of construction

Items affecting the cost estimate:

Items which may change the estimated construction cost include, but are not limited to:

  • Modifications to the scope of work included in this estimate.
  • Unforeseen sub-surface conditions.
  • Restrictive technical specifications or excessive contract conditions.
  • Any specified item of equipment, material, or product that cannot be obtained from at least three different sources.
  • Any non-competitive bid situations.
  • Bids delayed beyond the projected schedule.


The following assumptions have been made:

  1. Sufficient space will be provided to the contractor to house temporary site storage and accommodation within the vicinity of the site.
  2. Work will be carried out by union labor and during normal working hours.
  3. No restrictions on access to the site.


Prices in this opinion reflect current construction costs. We have included escalation to the midpoint of construction at a rate of 5% per annum for one year.


A design pricing contingency allowance has been included at 20%. This is to allow for items not included in the drawings or specifications and undefined at this stage, (including any addendums produced during bidding stage).

It is prudent for all program budgets to include an allowance for change orders, which occur during the construction phase and impact total project cost. This opinion does not include any such allowance, and it is our recommendation that the client carries in their program budget a percentage of 5% to 7% of the construction cost for this contingency.

Recommendation for Cost Control:

Hanscomb Inc. recommends that the owner, architect and engineers carefully review this document, including line item descriptions, unit prices, clarifications, exclusions, inclusions and assumptions, contingencies, escalation, and markups. If the project is over budget, or if there are unresolved budgeting issues, alternative systems/schemes should be evaluated before proceeding into the final design phase.

Requests for modifications of any apparent errors or omissions to this document must be made to Hanscomb within ten (10) days of receipt of this estimate. Otherwise, it will be understood that the contents have been concurred with and accepted.

It is recommended that a final update estimate be produced by Hanscomb Inc., using bid documents as well as all addenda, to determine overall cost of changes which may have occurred since the preparation of this estimate. The final update estimate will address changes and additions to the documents as well as addenda issued during the bidding process. Hanscomb cannot reconcile bid results to any estimate not produced from bid documents, including all addenda.

Cost Studies:

If the project is over budget or should there be a requirement to reduce the project cost, Hanscomb offers the additional service of Value Engineering. This service would involve preparation of cost studies and evaluation of alternates with subsequent recommendations as to the methods of reducing the project budget.


This opinion has been based on a competitive open bid situation with a recommended 5-7 bonafide reputable bids from general contractors and a minimum of 3 bidders for all items of sub-contracted work. Experience indicates that a lower number of bidders may result in higher bids, conversely an increased number of bidders may result in more competitive bids

Since Hanscomb has no control over the cost of labor, materials, or equipment, or over the contractor's method of determining prices, or over competitive bidding or market conditions, the opinion of probable construction cost provided for herein is made on the basis of professional expenence and qualifications. The opinion represents Hanscomb's best judgment as a professional construction consultant familiar with the construction industry. However, Hanscomb cannot and does not guarantee that the proposals, bids, or the construction cost will not vary from opinions of probable cost prepared by them.




Stage: Feasibility

% Of
1) Army Radio Station8,0004.2%
2) Electrical Connection Box2,0001.0%
3) Searchlight Shelter No. 1515,2007.9%
4) Searchlight Shelter No. 1822,80011.9%
5) Searchlight Shelter No. 1912,4006.5%
6) Generator Station for Searchlight Shelter No. 18 & 1916,1008.4%
7) Base End Station, Battery Mc Grath7,5003.9%
8) Battery End Station, Batteries Calef & Wilkeson3,7001.9%
9) Battery Commander Station, Batteries Calef & Wilkeson12,2006.4%
10) Base End Station at Billy Point (Battery White Base-End Station)7,2003.8%
11) Battery Commander Station and Base-End Station, Battery Humphreys12,7006.6%
12) Base End Station, Batteries Woodward & Grant16,8008.8%
13) Battery Commander Station and Base-End Station, Ashburn9,8005.1%
14) Battery Bluff, North Gun Emplacement1,1000.6%
15) Battery Bluff, South Gun Emplacement1,1000.6%
16) Battery Point Loma Panama Gun Mount3,3001.7%
17) Battery Point Loma Bunker Complex Guns 1 & 22,9001.5%
18) Battery Point Loma Bunker Complex Guns 3 & 42,9001.5%
19) Battery Point Loma Storeroom / Sleeping Quarters10,1005.3%

     Subtotal I167,80087.7%
     Abatement allowance20,00010.4%
     - additional mobilization allow3,6001.9%

Estimated Construction Contract Award (ECCA)$191,400100.0%

(detailed cost estimates for each structure omitted from the online edition)

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Last Updated: 06-Apr-2005