Free Revit Content by Manufacturers

Find Revit Free Library available 

It is always better to use same Revit library, what we specify. If the item is not available, download similar item and modify as per your need using family creation in REVIT.  

Autodesk Library 

http://seek.autodesk.com/

Architectural and Structural

http://www.usgdesignstudio.com/wallselector.asp

http://www.jeld-wen.com/architecturaltoolbox/index.cfm

http://www.kolbe-kolbe.com/architect/index.cfm?logintype=architect

http://www.strongtie.com/drawings/revit.asp

MEP
Hotwater tanks

http://www.hotwater.com/Resources/Product-Literature/Revit-Models/

Air handling units, Fan coils, condensing units, condenser, VAV terminalbox,  heat pumps
http://appliedair.com/building-information-modeling-bim.asp

http://www.mcquay.com/McQuay/BIM/Revit-BIMFiles

http://www.climatemaster.com/index/comm_literature

http://www.sierra-fas.com/building-information-modeling-bim.asp

http://www.tempriteheating.com/building-information-modeling-bim.asp

http://www.trane.com/Commercial/Products/product-templates/CadUserCategorySelect.aspx?i=1154

http://www.trane.com/commercial/AboutTrane/ContactUs/SalesOffices/BIMIntroduction.aspx

http://www.krueger-hvac.com/revit/

Split AC / Heat pump units 
http://www.mitsubishipro.com/en/professional/resources-and-tools?keywords=&res_type=REVIT%20Drawings&prod_cat=&prod_subcat=&mod_ver=

http://www.mitsubishipro.com/en/professional/resources-and-tools?keywords=&res_type=Revit

Cooling Tower
http://spxcooling.com/en/about/detail/revit-files/

Louvres, Fans, Grilles, Roof Curbs, Dampers etc
http://www.greenheck.com/drawings/
http://www.ruskin.com/revit.aspx
http://www.titus-hvac.com/software/revit/Revit.asp
http://www.lorencook.com/About/destools.htm#2
http://www.price-hvac.com/software/revit/
http://tuttleandbailey.com/site/site/revit.aspx

Plumbing fixtures and Back flow preventer 
http://www.americanstandard-us.com/resources/
http://www.us.kohler.com/tech/cadsymbol/cadsymbol.jsp?nsection=1&nsubsection=1&nitem=link8
http://www.lorencook.com/About/destools.htm#2
http://www.sloanvalve.com/Customer_Care/Technical_Downloads.aspx
http://www.watts.com/pages/whatsnew/3dCAD.asp
http://www.bradleycorp.com/bim/products/bim
http://www.watts.com/pages/whatsnew/3dCAD.asp

Hydronic : Pumps, Expansion tanks, Air separators, Suction diffusers, Heat-exchanger
http://www.taco-hvac.com/en/cad_wizard.htmlTrane

Victaulic coupling
http://www.victaulic.com/content/cadandsoftware.htm

Control Valves, Fire sprinklers
http://www.vikinggroupinc.com/resources/revit-files-0

Electrical

Lighting
http://www.acuitybrandslighting.com/BIM/
http://www.focalpointlights.com/resources/BIM.html
http://www.lightolier.com/resources/downloads.jsp#BIM
http://www.visalighting.com/site/resources/bim-building-information-modeling
http://www.focalpointlights.com/resources/BIM.html
http://www.arcat.com/bim/clients/hubbell.html?coid=33138
http://www.hubbelllighting.com/resources/bim_files.php 
Elevators:
https://www.digipara.com/downloads/free-digipara-elevatorarchitect/
http://www.arcat.com/bim/divs/14-142000-savaria.shtml
http://bimcreate.otis.com/
http://www.revit-content.com/content/elevator/
 

Mono system
http://www.monosystems.com/

Network Infrastructure hardware
http://www.siemon.com/us/download/bim.asp

Other Free Revit Content :
http://revit.autodesk.com/library/html/
http://www.arcat.com/bim/bim_objects.shtml
http://www.revitcity.com
http://www.revitforum.org/showthread.php?98-Manufacturers-providing-Revit-MEP-Families

Best for All generic  Families  :
http://www.arcat.com/bim/bim_objects.shtml