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Renovating the fail wi11 requia~e banging ~.~e site up to crude i.n many area. tine which plays a significant part In ~'~AC is the outdoor air requirement, Replacing the current air conditia~ung s stems ~~rill re wire an increased amount of outdoor air to be brougl~t into the wilding to n~eel Y q .. the North Carolina State ~ecl~anical Code ~Chapte~~ 4~ and Asl~rae Standard d2. Thrs zs done to increase tl~e indoor air uali within the 'aid ~by providing fresh air fro~r~ the outside and q ~ ~. exhausting stale air containing odors, contaminants, etc. from the building. We also ex~lared the a~tian of applying ~a district heating system to this building and ada~en~ buildings in the area. ~e do: not recommend districting as an option for this site. fur recom~nendatian Is based upon this site having a relatively lbw load density and a lair annual load factor. A. lave load density means that the heating a~~d Gaoling loads are spread out over a .............:....... ................. . large geographical area with large areas haviaag no load a~ all ~stree~s, parking lots, grass areas, etc,}. A low annual 1Qad factor means that due tv these buildings being mostly af~:Ge areas the loads fluctuate sig~uflcantly on a daily and yearly basis. Tl~e ~Qa~ Ashrae ~andbaok ~- H~'AC Systems and ~quiprnent Chapter 11 } reco~ximends that both of these factors be high in order for the ecananucs of a district heating and cooling to make sense. This is typically Seen in 1} Indust~~ial complexes and ~~ high rise buildings where you have a high heating and cooling load ~er s u~are fr~ot of site footprint and mare consistent daily and yearly load factors. p q Also, the cast of the distribution,plping for this system would be very large and installation s1 'fica~~tl disru t the roads sidewalks and ass areas around the buildings ~ phis would got y p ~ ~' l~istor~c area. The coordinafiian with existing utilities and doe "unknowns" below these areas alone could present a significant challenge and in itself could prove prohibitive. Althou~ h not analyzed in. this life cycle cast analysis, ire considered the options for dealing v~ith g . 13V.AC related issues .at the Historic Courthouse and the Court Street Annex. Since a d~~ti~et s stem is~ not ~ racncal ore recornrnend re lacing the equipment at the ~3i5toric Courthouse v~rth y p ~ p like equipment or substituting D~ systems in lieu of ~WS~,'. As for tlae ~a~urt Street Annex, we recommend abandoning the ~underslah ductwork en~ixely a~ it can became prob~en~atic with res ~ ect to hu~nidi and indoor air quality. The limited above ce`~ing space prahibi~ts Installing A ~ duct~tr~ark above ceiling so ~~re would xeea~n,mend small, ductless I~~ systems such as Mitsubishi's Ci ~ul~i system to treat the laver level. These systems aerate well at lour load ~ . . co~nditians,providing .some degree of dehunlidi~catian at even the lowest load points. Cansideang that the equipme~.t ~erving the second. Level is relatively new ~i ~~9 0~• late~~} we don't see an need to rnad~fy ar .replace this equipment at this tlrne. Y ~AS1C S~"STFI~ D~S1C~1 C~IT~RIA The eventual s stem design, aver cand`ucting the life cycle cost analysis on the three systems ~' ~ ~ r ~ . listed above and selecring an alternative, would ~t~clude the follow~n.g abut not lnn~ted to}. ~~ Evaluation of the existing central chiller and air Dandling units, tr} dete~~rnlne haw they should be replaced within the pra~ect, budget. ~ Instal~atian of a new e~~ergy nanagement system.