How do I rid my house of an infestation of harvestmen spiders?

I don't know about how to deal with any specific type (Harvestman) of spider, but we had a general infestation one year of several types of spiders and bugs. At a hardware store (or I bet even somewhere like Walmart or Kmart) they have these electric devices you can plug in that emit a super high frequency that only spiders and other bugs can hear. It irritates them to the point that they won't build their nests in the house and eventually they leave. They cover a couple rooms each when placed in strategic areas. I think they ran about 15-20 bucks each if I remember.

The pitch is too high for dogs and cats to hear, so it does not bother them if you have them. Our dogs showed no signs of noticing it other than a slight jerk of the head and prick of the ears when we first plugged it in and then they just went back to what they were doing and forgot about it. Worked for us as well because we have do have the dogs and we didn't want to spray any chemicals in the house that might harm them if they ingested it. Also you don't end up with a house full of icky dead bugs to clean up.

Good luck.

Here's an example of what I mean: http://www.pestrepellerultimate.com/

Those seem more expensive than the ones we picked up but they appear to cover the whole house and might be more high tech. The cheaper ones we got worked just fine though.

We have the same problem and we are in a newbuild house. Everyday there is 1-2 appearing in our living room. Its so bizare as I always thought these creatures remained outside. I've got some spider stop spray and intend to spray all the windows and doors in the hope it stops them. Also got a plug in as suggested earlier. Hope she sorts it out.

I would suggest a professional bug killer. It sounds like they are infested in the whole house.

if her house is drying out i had underfloor heating installed and when the screed was drying out i had a lot of spiders you might need the house fumigated call in the specialists