Most office buildings are closed up by nature and will usually leave most of the office workers in the building feeling closed up and claustrophobic themselves. This in turn will reduce the productivity in your office because people who are feeling uncomfortable will not be able to work to the best of their ability and therefore, it is your duty as the owner of the company to make sure that your staff is as comfortable as possible.
Add in more ventilation
If you are able to do so, bring in a builder and have him add more ventilation to the office in the form of windows and other openings. However, this may not always be possible and your next best option is to add in a high standard ducted air conditioning which will clear the air. There are many benefits to air conditioning but there are also negative aspects to it including the huge electrical bill that you will be faced with at the end of the month.
If there are any sealed doors, windows or openings in your office, it is important for you to have renovations done on your office to have these all opened up. You might be surprised to find that there are many sealed openings. If the people who worked in your office before you hired it had their own ducted air conditioner, they would have needed to ensure that the office is air tight and a closed, sealed space in order to get the better cooling product and this is why they may have had all openings sealed. You will find that if you unseal all of these doors, windows and other openings, your problem with the office will be immediately solved.
If you feel that one of your staff is especially bothered by the closed up space that your office is, you could even try to help this particular person by moving her to a place where there is more ventilation and help her to feel better.
If you have no other option to open the office up, you will need to invest on air conditioning. Although this is likely to cost you a little extra money, you can be assured that this will be an investment because your staff will work harder and better in a comfortable environment and you can be guaranteed to get a better output from the work that is being done if your staff is happy and comfortable. You may want to consider speaking to an engineer or a builder to ask them for their opinion on what else can be done.